title: Porous Alumina Based Capacitive MEMS RH Sensor

abstract:
  The aim of a joint research and development project at the BME and HWU is to
produce a cheap, reliable, low-power and CMOS-MEMS process compatible
capacitive type relative humidity (RH) sensor that can be incorporated into a
state-of-the-art, wireless sensor network. In this paper we discuss the
preparation of our new capacitive structure based on post-CMOS MEMS processes
and the methods which were used to characterize the thin film porous alumina
sensing layer. The average sensitivity is approx. 15 pF/RH% which is more than
a magnitude higher than the values found in the literature. The sensor is
equipped with integrated resistive heating, which can be used for maintenance
to reduce drift, or for keeping the sensing layer at elevated temperature, as
an alternative method for temperature-dependence cancellation.


title: Integrated RF MEMS/CMOS Devices

abstract:
  A maskless post-processing technique for CMOS chips is developed that enables
the fabrication of RF MEMS parallel-plate capacitors with a high quality factor
and a very compact size. Simulations and measured results are presented for
several MEMS/CMOS capacitors. A 2-pole coupled line tunable bandpass filter
with a center frequency of 9.5 GHz is designed, fabricated and tested. A tuning
range of 17% is achieved using integrated variable MEMS/CMOS capacitors with a
quality factor exceeding 20. The tunable filter occupies a chip area of 1.2 x
2.1 mm2.


title: Design Methodology and Manufacture of a Microinductor

abstract:
  Potential core materials to supersede ferrite in the 0.5-10 MHz frequency
range are investigated. The performance of electrodeposited nickel-iron,
cobalt-iron-copper alloys and the commercial alloy Vitrovac 6025 have been
assessed through their inclusion within a custom-made solenoid microinductor.
Although the present inductor, at 500 KHz, achieves 77% power efficiency for
24.7W/cm3 power density, an optimized process predicts a power efficiency of
97% for 30.83W/cm3 power density. The principle issues regarding microinductor
design and performance are discussed.


title: Megasonic Enhanced Electrodeposition

abstract:
  A novel way of filling high aspect ratio vertical interconnection (microvias)
with an aspect ratio of >2:1 is presented. High frequency acoustic streaming at
megasonic frequencies enables the decrease of the Nernst-diffusion layer down
to the sub-micron range, allowing thereby conformal electrodeposition in deep
grooves. Higher throughput and better control over the deposition properties
are possible for the manufacturing of interconnections and metal-based MEMS.


title: UV Direct-Writing of Metals on Polyimide

abstract:
  Conductive micro-patterned copper tracks were fabricated by UV direct-writing
of a nanoparticle silver seed layer followed by selective electroless copper
deposition. Silver ions were first incorporated into a hydrolyzed polyimide
surface layer by wet chemical treatment. A photoreactive polymer coating,
methoxy poly(ethylene glycol) (MPEG) was coated on top of the substrate prior
to UV irradiation. Electrons released through the interaction between the MPEG
molecules and UV photons allowed the reduction of the silver ions across the
MPEG/doped polyimide interface. The resultant silver seed layer has a cluster
morphology which is suitable for the initiation of electroless plating. Initial
results showed that the deposited copper tracks were in good agreement with the
track width on the photomask and laser direct-writing can also fabricate
smaller line width metal tracks with good accuracy. The facile fabrication
presented here can be carried out in air, at atmospheric pressure, and on
contoured surfaces.


title: Micro Embossing of Ceramic Green Substrates for Micro Devices

abstract:
  Multilayered ceramic substrates with embedded micro patterns are becoming
increasingly important, for example, in harsh environment electronics and
microfluidic devices. Fabrication of these embedded micro patterns, such as
micro channels, cavities and vias, is a challenge. This study focuses on the
process of patterning micro features on ceramic green substrates using micro
embossing. A ceramic green tape that possessed near-zero shrinkage in the x-y
plane was used, six layers of which were laminated as the embossing substrate.
The process parameters that impact on the pattern fidelity were investigated
and optimized in this study. Micro features with line-width as small as several
micrometers were formed on the ceramic green substrates. The dynamic
thermo-mechanical analysis indicated that extending the holding time at certain
temperature range would harden the green substrates with little effect on
improving the embossing fidelity. Ceramic substrates with embossed micro
patterns were obtain d after co-firing. The embedded micro channels were also
obtained by laminating the green tapes on the embossed substrates.


title: Characterization and Modeling of an Electro-thermal MEMS Structure

abstract:
  Thermal functional circuits are an interesting and perspectivic group of the
MEMS elements. A practical realization is called Quadratic Transfer
Characteristic (QTC) element which driving principle is the Seebeck-effect. In
this paper we present the analyses of a QTC element from different
perspectives. To check the real behavior of the device, we measured a few,
secondary properties of the structure which correspond to special behavior
because these properties can not be easily derived from the main
characteristics.


title: Measurement of Large Forces and Deflections in Microstructures

abstract:
  Properties of typical MEMS materials have been widely investigated.
Mechanical properties of MEMS structures depend not only on the bulk material
properties, but also structural factors. A measurement system has been made to
measure force/deflection on microstructures to examine some of the structural
properties. This is a stylus setup integrated with a load cell and a linear
actuator. First, the requirements for the measurement system were established.
Then the system was built up and characterized. We have successfully made
measurements on a typical micromechanical structure, a cantilever accelerometer
design. The stylus placement accuracy, the spring constant along the proof
mass, analysis of the force/deflection curve shape and destructive tests on the
cantilever have been investigated in our experiment and will be presented in
this paper.


title: Contactless Thermal Characterization of High Temperature Test Chamber

abstract:
  In this paper the methodology and the results of a contactless thermal
characterization of a high temperature test chamber will be introduced. The
test chamber is used for fatigue testing of different MEMS devices where the
homogenous temperature distribution within the close proximity from the heating
filaments is very important. Our aim was to characterize the evolving
temperature distribution inside the test chamber. In order to achieve smaller
time constant a new contactless sensor card was developed. The contactless
thermal characterization method introduced in this paper enables in situ heat
distribution measurement inside the test chamber during operation, with the
detection of potentially uneven heat distribution.


title:
Processing and Characterization of Precision Microparts from
  Nickel-based Materials

abstract:
  The objective of this research was to study the influence of electroplating
parameters on electrodeposit characteristics for the production of nickel (Ni)
and nickel-iron (Ni-Fe) microparts by photoelectroforming. The research focused
on the most relevant parameter for industry, which is the current density,
because it determines the process time and the consumed energy. The results of
the Ni and Ni-Fe characterisations can be divided into two aspects closely
linked with each other ; the morphology and the hardness.


title:
On the Eigenspaces of Lamplighter Random Walks and Percolation Clusters
  on Graphs

abstract:
  We show that the Plancherel measure of the lamplighter random walk on a graph
coincides with the expected spectral measure of the absorbing random walk on
the Bernoulli percolation clusters. In the subcritical regime the spectrum is
pure point and we construct a complete orthonormal basis of finitely supported
eigenfunctions.


title:
Manufacturing of A micro probe using supersonic aided electrolysis
  process

abstract:
  In this paper, a practical micromachining technology was applied for the
fabrication of a micro probe using a complex nontraditional machining process.
A series process was combined to machine tungsten carbide rods from original
dimension. The original dimension of tungsten carbide rods was 3mm ; the rods
were ground to a fixed-dimension of 50 micrometers using precision grinding
machine in first step. And then, the rod could be machined to a
middle-dimension of 20 micrometers by electrolysis. A final desired micro
dimension can be achieved using supersonic aided electrolysis.
High-aspect-ratio of micro tungsten carbide rod was easily obtained by this
process. Surface roughness of the sample with supersonic aided agitation was
compared with that with no agitation in electrolysis. The machined surface of
the sample is very smooth due to ionized particles of anode could be removed by
supersonic aided agitation during electrolysis. Deep micro holes can also be
achieved by the machined high-aspect-rati tungsten carbide rod using EDM
process. A micro probe of a ball shape at the end was processed by proposed
supersonic aided electrolysis machining process.


title: The effect of classical noise on a quantum two-level system

abstract:
  We consider a quantum two-level system perturbed by classical noise. The
noise is implemented as a stationary diffusion process in the off-diagonal
matrix elements of the Hamiltonian, representing a transverse magnetic field.
We determine the invariant measure of the system and prove its uniqueness. In
the case of Ornstein-Uhlenbeck noise, we determine the speed of convergence to
the invariant measure. Finally, we determine an approximate one-dimensional
diffusion equation for the transition probabilities. The proofs use both
spectral-theoretic and probabilistic methods.


title: Remarks on string solitons

abstract:
  We consider generalized self-duality equations for U(2r) Yang-Mills theory on
R^8 with quaternionic structure. We employ the extended ADHM method in eight
dimensions to construct exact soliton solutions of the low-energy effective
theory of the heterotic string.


title: Large Area Roller Embossing of Multilayered Ceramic Green Composites

abstract:
  In this paper, we will report our achievements in developing large area
patterning of multilayered ceramic green composites using roller embossing. The
aim of our research is to pattern large area ceramic green composites using a
modified roller laminating apparatus, which is compatible with screen printing
machines, for integration of embossing and screen printing. The instrumentation
of our roller embossing apparatus, as shown in Figure1, consists of roller 1
and rollers 2. Roller 1 is heated up to the desired embossing temperature ;
roller 2 is, however, kept at room temperature. The mould is a nickel template
manufactured by plating nickel-based micro patterns (height : 50 $\mu$m) on a
nickel film (thickness : 70 $\mu$m) ; the substrate for the roller embossing is
a multilayered Heraeus Heralock HL 2000 ceramic green composite. Comparing with
the conventional simultaneous embossing, the advantages of roller embossing
include : (1) low embossing force ; (2) easiness of demoulding ; (3) localized
area in contact with heater ; and etc. We have demonstrated the capability of
large area roller embossing with a panel size of 150mmx 150mm on the mentioned
substrate. We have explored and confirmed the impact of parameters (feed speed,
temperature of roller and applied pressure) to the pattern quality of roller
embossing. Furthermore, under the optimized process parameters, we
characterized the variations of pattern dimension over the panel area, and
calculated a scaling factor in order to make the panel compatible with other
processes. Figure 2 shows the embossed patterns on a 150mmx 150mm green ceramic
panel.


title:
Study of mechanical response in embossing of ceramic green substrate by
  micro-indentation

abstract:
  Micro-indentation test with a micro flat-end cone indenter was employed to
simulate micro embossing process and investigate the thermo-mechanical response
of ceramic green substrates. The laminated low temperature co-fired ceramic
green tapes were used as the testing material ; the correlations of indentation
depth versus applied force and applied stress at the temperatures of 25 degrees
C and 75degrees C were studied. The results showed that permanent indentation
cavities could be formed at temperatures ranging from 25 degrees C to 75
degrees C, and the depth of cavities created was applied force, temperature and
dwell time dependent. Creep occurred and made a larger contribution to the
plastic deformation at elevated temperatures and high peak loads. There was
instantaneous recovery during the unloading and retarded recovery in the first
day after indentation. There was no significant pile-up due to material flow
observed under compression at the temperature up to 75 degrees C. The plastic
deformation was the main cause for formation of cavity on the ceramic green
substrate under compression. The results can be used as a guideline for
embossing ceramic green substrates.


title:
Top-Down Behavioral Modeling Methodology of a Piezoelectric
  Microgenerator For Integrated Power Harvesting Systems

abstract:
  In this study, we developed a top/down methodology for behavioral and
structural modeling of multi-domain microsystems. Then, we validated this
methodology through a study case : a piezoelectric microgenerator. We also
proved the effectiveness of VHDL-AMS language not only for modeling in
behavioral and structural levels but also in writing physical models that can
predict the experimental results. Finally, we validated these models by
presenting and discussing simulations results.


title:
Hybridization of Magnetism and Piezoelectricity for an Energy Scavenger
  based on Temporal Variation of Temperature

abstract:
  Autonomous microsystems are confronted today to a major challenge : the one
of energy supply. Energy scavenging, i.e. collecting energy from the ambient
environment has been developed to answer this problematic. Various sources have
already been successfully used (solar, vibration). This article presents
temporal variations of temperature as a new source of exploitable energy. A
brief review will take place at the beginning, exposing the different
approaches used in the past. Then we will focus our attention on hybridization
of magnetism and piezoelectricity. A new kind of thermal generator is proposed
and a preliminary model is exposed. Conclusions will be drawn on the
suitability of this prototype and the improvements that are needed to increase
its potential.


title: Testing GRBs as Standard Candles

abstract:
  Several correlations among Gamma Ray Burst (GRB) observables with available
redshifts have been recently identified. Proper evaluation and calibration of
these correlations may facilitate the use of GRBs as standard candles
constraining the expansion history of the universe up to redshifts of $z>6$.
Here we use the 69 GRB dataset recently compiled by Schaefer (astro-ph/0612285)
and we test the calibration of five of the above correlations
($1:\epkk-E_\gamma$, $2:\epkk-L$, $3:\tlag-L$, $4:V-L$, $5:\trt-L$) with
respect to two potential sources of systematics: Evolution with redshift and
cosmological model used in the calibration. In examining the model dependence
we assume flat \lcdm and vary $\omm$. Our approach avoids the circularity
problem of previous studies since we do not fix $\omm$ to find the correlation
parameters. Instead we simultaneously minimize $\chi^2$ with respect to both
the log-linear correlation parameters $a$, $b$ and the cosmological parameter
$\omm$. We find no statistically significant evidence for redshift dependence
of $a$ and $b$ in any of the correlation relations tested. We also find that
one of the five correlation relations tested ($\epkk-E_\gamma$) has a
significantly lower intrinsic dispersion compared to the other correlations.
For this correlation relation, the maximum likelihood method favors the
existence of a cosmological constant while the other four correlation favor a
flat matter dominated universe $\omm \simeq 1$. Finally, a cross-correlation
analysis between the GRBs and SnIa data for various values of $\omm$ has shown
that the $E_{peak}-E_\gamma$ relation traces well the SnIa redshift regime.
However, even the tightest correlation relation ($E_{peak}-E_\gamma$) provides
much weaker constraints on $\omm$ than current SnIa data.


title:
Simulation of an Electrostatic Energy Harvester at Large Amplitude
  Narrow and Wide Band Vibrations

abstract:
  An electrostatic in-plane overlap varying energy harvester is modeled and
simulated using a circuit simulator. Both linear and nonlinear models are
investigated. The nonlinear model includes mechanical stoppers at the
displacement extremes. Large amplitude excitation signals, both narrow and wide
band, are used to emulate environmental vibrations. Nonlinear behavior is
significant at large displacement due to the impact on mechanical stoppers. For
a sinusoidal excitation the mechanical stoppers cause the output power to
flatten and weakly decrease. For a wide band excitation, the output power first
increases linearly with the power spectral density of the input signal, then
grows slower than linearly.


title:
Optimization and AMS Modeling for Design of an Electrostatic Vibration
  Energy Harvester's Conditioning Circuit with an Auto-Adaptive Process to the
  External Vibration Changes

abstract:
  Electrostatic transducers for vibration energy scavenging have been an object
to numerous studies, but are still facing major issues relating to their
conditioning circuit. One of the most popular ones uses a charge pump and a
flyback circuit based on a Buck DC-DC converter (Fig. 1). A commutation between
the energy accumulation in the charge pump and the recharge of the buffer
capacitor Cres is assured by a switch which is the major bottleneck in the
energy harvester circuit. The commutation timing of the switch determines the
efficiency of the energy harvesting. In previous papers [1] the switch
commutates periodically with some fixed duty ratio. However, this solution is
not appropriate when the environment parameters, e.g. the vibration frequency,
change. We found that the switching should be ordered by the internal state of
the circuit, an not by some fixed timing scenario. We presents how to find the
optimal operation mode of the harvester. To validate the study, the system was
modeled using a mixed VHDL-AMS - ELDO model.


title: Design of parametrically forced patterns and quasipatterns

abstract:
  The Faraday wave experiment is a classic example of a system driven by
parametric forcing, and it produces a wide range of complex patterns, including
superlattice patterns and quasipatterns. Nonlinear three-wave interactions
between driven and weakly damped modes play a key role in determining which
patterns are favoured. We use this idea to design single and multi-frequency
forcing functions that produce examples of superlattice patterns and
quasipatterns in a new model PDE with parametric forcing. We make quantitative
comparisons between the predicted patterns and the solutions of the PDE.
Unexpectedly, the agreement is good only for parameter values very close to
onset. The reason that the range of validity is limited is that the theory
requires strong damping of all modes apart from the driven pattern-forming
modes. This is in conflict with the requirement for weak damping if three-wave
coupling is to influence pattern selection effectively. We distinguish the two
different ways that three-wave interactions can be used to stabilise
quasipatterns, and present examples of 12-, 14- and 20-fold approximate
quasipatterns. We identify which computational domains provide the most
accurate approximations to 12-fold quasipatterns, and systematically
investigate the Fourier spectra of the most accurate approximations.


title:
Fabrication of Nanostructured PLGA Scaffolds Using Anodic Aluminum Oxide
  Templates

abstract:
  PLGA (poly(lactic-co-glycolic acid)) is one of the most used biodegradable
and biocompatible materials. Nanostructured PLGA even has great application
potentials in tissue engineering. In this research, a fabrication technique for
nanostructured PLGA membrane was investigated and developed. In this novel
fabrication approach, an anodic aluminum oxide (AAO) film was use as the
template ; the PLGA solution was then cast on it ; the vacuum air-extraction
process was applied to transfer the nano porous pattern from the AAO membrane
to the PLGA membrane and form nanostures on it. The cell culture experiments of
the bovine endothelial cells demonstrated that the nanostructured PLGA membrane
can double the cell growing rate. Compared to the conventional chemical-etching
process, the physical fabrication method proposed in this research not only is
simpler but also does not alter the characteristics of the PLGA. The
nanostructure of the PLGA membrane can be well controlled by the AAO temperate.


title:
High Performance Microreactor for Rapid Fluid Mixing and Redox Reaction
  of Ascorbic Acid

abstract:
  A novel micro device with a mechanism of split and recombination (SNR) for
rapid fluidic mixing and reaction, named a SNR micro-reactor, was designed,
fabricated and systematically analyzed. This SNR micro-reactor possessing an
in-plane dividing structure requires only simple fabrication. We investigated
this reactor and compared it numerically and experimentally with a
slanted-groove micromixer (SGM). From the numerical results the mixing indices
and mixing patterns demonstrated that the mixing ability of the SNR
micro-reactor was much superior to that of the SGM. From a mixing test with
phenolphthalein and sodium hydroxide solutions, the mixing lengths of the SNR
micro-reactor were less than 4 mm for a Reynolds number over a wide range (Re =
0.1 - 10). From a comparison of mixing lengths, the results revealed also that
the SNR micro-reactor surpassed the SGM in mixing performance by more than 200
%. As a reaction length is a suitable test of the performance of a reactor, we
introduced a redox reaction between ascorbic acid and iodine solutions to
assess the reaction capability of these micro devices ; the reaction lengths of
the SNR micro-reactor were much shorter than those of a SGM. The SNR
micro-reactor has consequently a remarkable efficiency for fluid mixing and
reaction.


title:
Cell Trapping Utilizing Insulator-based Dielectrophoresis in The
  Open-Top Microchannels

abstract:
  The ability to manipulate or separate a biological small particle, such as a
living cell and embryo, is fundamental needed to many biological and medical
applications. The insulator-based dielectrophoresis (iDEP) trapping is composed
of conductless tetragon structures in micro-chip. In this study, a lower
conductive material of photoresist was adopted as a structure in open-top
microchannel instead of a metallic wire to squeeze the electric field in a
conducting solution, therefore, creating a high field gradient with a local
maximum. The microchip with the open-top microchannels was designed and
fabricated herein. The insulator-based DEP trapping microchip with the open-top
microchannels was designed and fabricated in this work. The cells trapped by
DEP force could be further treated or cultured in the open-top microchannel ;
however, those trapped in the microchip with enclosed microchannels could not
be proceeded easily.


title: Design and Analysis of a Chaotic Micromixer with Vortices Modulation

abstract:
  A novel design for vortex modulation of a passive chaotic micromixer, named a
circulation-disturbance micromixer (CDM), has been achieved and analyzed
experimentally and numerically. The systematic numerical analyses - topological
flow characteristics and particle tracking method - have been developed, that
enable visualization of detailed mixing patterns. To display the cross section
of mixing region of flows in our CDM, the biotin-streptavidin binding is
detected through the fluorescence resonance energy transfer (FRET) pair of
fluorescent proteins - R-phycoerythrin (RPE) and cross-linked allophycocyanin
(clAPC). We expect the diagnosis technique using FRET will be successfully
applied to biochemical analysis in microfluidic system.


title: Portable Valve-less Peristaltic Micro-pump Design and Fabrication

abstract:
  This paper is to describe a design and fabrication method for a valve-less
peristaltic micro-pump. The valve-less peristaltic micro-pump with three
membrane chambers in a serial is actuated by three piezoelectric (PZT)
actuators. With the fluidic flow design, liquid in the flow channel is pumped
to a constant flow speed ranged from 0.4 to 0.48 mm/s. In term of the maximum
flow rate of the micro-pump is about 365 mircoliters/min, when the applied
voltage is 24V and frequency 50 Hz. Photolithography process was used to
fabricate the micro-pump mold. PDMS molding and PDMS bonding method were used
to fabricate the micro-channel and actuator chambers. A portable drive
controller was designed to control three PZT actuators in a proper sequence to
drive the chamber membrane. Then, all parts were integrated into the portable
valve-less peristaltic micro-pump system.


title:
Microfluidic Device for Continuous Magnetophoretic Separation of Red
  Blood Cells

abstract:
  This paper presents a microfluidic device for magnetophoretic separation red
blood cells from blood under contionous flow. The separation method consist of
continous flow of a blood sample (diluted in PBS) through a microfluidic
channel which presents on the bottom "dots" of feromagnetic layer. By appling a
magnetic field perpendicular on the flowing direction, the feromagnetic "dots"
generates a gradient of magnetic field which amplifies the magnetic force. As a
result, the red blood cells are captured on the bottom of the microfluidic
channel while the rest of the blood is collected at the outlet. Experimental
results show that an average of 95 % of red blood cells are trapped in the
device


title:
Fabrication of Embedded Microvalve on PMMA Microfluidic Devices through
  Surface Functionalization

abstract:
  The integration of a PDMS membrane within orthogonally placed PMMA
microfluidic channels enables the pneumatic actuation of valves within bonded
PMMA-PDMS-PMMA multilayer devices. Here, surface functionalization of PMMA
substrates via acid catalyzed hydrolysis and air plasma corona treatment were
investigated as possible techniques to permanently bond PMMA microfluidic
channels to PDMS surfaces. FTIR and water contact angle analysis of
functionalized PMMA substrates showed that air plasma corona treatment was most
effective in inducing PMMA hydrophilicity. Subsequent fluidic tests showed that
air plasma modified and bonded PMMA multilayer devices could withstand fluid
pressure at an operational flow rate of 9 mircoliters/min. The pneumatic
actuation of the embedded PDMS membrane was observed through optical microscopy
and an electrical resistance based technique. PDMS membrane actuation occurred
at pneumatic pressures of as low as 10kPa and complete valving occurred at
14kPa for 100 micrometers x 100 micrometers channel cross-sections.


title: Cut Points and Diffusions in Random Environment

abstract:
  In this article we investigate the asymptotic behavior of a new class of
multi-dimensional diffusions in random environment. We introduce cut times in
the spirit of the work done by Bolthausen, Sznitman and Zeitouni, see [4], in
the discrete setting providing a decoupling effect in the process. This allows
us to take advantage of an ergodic structure to derive a strong law of large
numbers with possibly vanishing limiting velocity and a central limit theorem
under the quenched measure.


title: Hot Roller Embossing for the Creation of Microfluidic Devices

abstract:
  We report on the hot roller embossing of polymer sheets for the creation of
microfluidic structures. Measurements conducted on 100 $\mu$m features showed
that the lateral dimensions could be replicated to within 2% tolerance, while
over 85% of mould depth was embossed. Feature sizes down to 50 $\mu$m and
feature depths up to 30 $\mu$m had been achieved. At lower temperatures,
asymmetric pile up of polymer material outside embossed regions was observed
with higher pile up occurring on the trailing side of the embossed regions.


title:
Geometrical Variation Analysis of an Electrothermally Driven Polysilicon
  Microactuator

abstract:
  The analytical models that predict thermal and mechanical responses of
microactuator have been developed. These models are based on electro thermal
and thermo mechanical analysis of the microbeam. Also, Finite Element Analysis
(FEA) is used to evaluate microactuator tip deflection. Analytical and Finite
Element results are compared with experimental results in literature and show
good agreement in low input voltages. A dimensional variation of beam lengths,
beam lengths ratios and gap are introduced in analytical and FEA models to
explore microactuator performance. An electrothermally driven polysilicon
microactuator similar to Pan's actuator architecture has been studied in this
paper. This microactuator generates deflection through asymmetric heating of
the hot and cold polysilicon arms with different lengths. For this
microactuator architecture, an optimal beam length ratio equal to 0.46 has been
obtained to achieve maximum tip deflection. . As it was expected, the results
show decreasing air gap increase microactuator tip deflection. It is also found
that for microactuators with longer hot arms, microactuator tip deflections are
more sensitive to beam length ratios and air gap.


title: In-Plane Bistable Nanowire For Memory Devices

abstract:
  We present a nanomechanical device design to be used in a non-volatile
mechanical memory point. The structure is composed of a suspended slender
nanowire (width : 100nm, thickness 430nm length : 8 to 30$\mu$m) clamped at its
both ends. Electrodes are placed on each sides of the nanowire and are used to
actuate the structure (writing, erasing) and to measure the position through a
capactive bridge (reading). The structure is patterned by electron beam
lithography on a pre-stressed thermally grown silicon dioxide layer. When later
released, the stressed material relaxes and the beam buckles in a position of
lower energy. Such symmetric beams, called Euler beams, show two stable
deformed positions thus form a bistable structure. This paper will present the
fabrication, simulation and mechanical and electrical actuation of an in plane
bistable nanowire. Final paper will include a section on FEM simulations.


title: RF-MEMS Switched Varactors for Medium Power Applications

abstract:
  In RF (Radio Frequency) domain, one of the limitations of using MEMS (Micro
Electromechanical Systems) switching devices for medium power applications is
RF power. Failure phenomena appear even for 500 mW. A design of MEMS switched
capacitors with an enhanced topology is presented in this paper to prevent it.
This kind of device and its promising performances will serve to fabricate a
MEMS based phase shifter able to work under several watts.


title: Low-Drift Flow Sensor with Zero-Offset Thermopile-Based Power Feedback

abstract:
  A thermal flow sensor has been realised consisting of freely-suspended
silicon-rich silicon-nitride microchannels with an integrated Al/poly-Si++
thermopile in combination with up- and downstream Al heater resistors. The
inherently zero offset of the thermopile is exploited in a feedback loop
controlling the dissipated power in the heater resistors, eliminating
inevitable influences of resistance drift and mismatch of the thin-film metal
resistors. The control system cancels the flow-induced temperature difference
across the thermopile by controlling a power difference between both heater
resistors, thereby giving a measure for the flow rate. The flow sensor was
characterised for power difference versus water flow rates up to 1.5 ul/min,
being in good agreement with a thermal model of the sensor, and the correct
low-drift operation of the temperature-balancing control system has been
verified.


title: Single Chip Sensing of Multiple Gas Flows

abstract:
  The fabrication and experimental characterization of a thermal flow meter,
capable of detecting and measuring two independent gas flows with a single
chip, is described. The device is based on a 4 x 4 mm2 silicon chip, where a
series of differential micro-anemometers have been integrated together with
standard electronic components by means of postprocessing techniques. The
innovative aspect of the sensor is the use of a plastic adapter, thermally
bonded to the chip, to convey the gas flow only to the areas where the sensors
are located. The use of this inexpensive packaging procedure to include
different sensing structures in distinct flow channels is demonstrated.


title:
Comparison Between Damping Coefficients of Measured Perforated
  Micromechanical Test Structures and Compact Models

abstract:
  Measured damping coefficients of six different perforated micromechanical
test structures are compared with damping coefficients given by published
compact models. The motion of the perforated plates is almost translational,
the surface shape is rectangular, and the perforation is uniform validating the
assumptions made for compact models. In the structures, the perforation ratio
varies from 24% - 59%. The study of the structure shows that the
compressibility and inertia do not contribute to the damping at the frequencies
used (130kHz - 220kHz). The damping coefficients given by all four compact
models underestimate the measured damping coefficient by approximately 20%. The
reasons for this underestimation are discussed by studying the various flow
components in the models.


title:
A piecewise-linear reduced-order model of squeeze-film damping for
  deformable structures including large displacement effects

abstract:
  This paper presents a reduced-order model for the Reynolds equation for
deformable structure and large displacements. It is based on the model
established in [11] which is piece-wise linearized using two different methods.
The advantages and drawbacks of each method are pointed out. The pull-in time
of a microswitch is determined and compared to experimental and other
simulation data.


title:
RF-MEMS beam components : FEM modelling and experimental identification
  of pull-in in presence of residual stress

abstract:
  In this paper an experimental validation of numerical approaches aimed to
predict the coupled behaviour of microbeams for out-of-plane bending tests is
performed. This work completes a previous investigation concerning in plane
microbeams bending. Often out-of-plane microcantilevers and clamped-clamped
microbeams suffer the presence of residual strain and stress, which affect the
value of pull-in voltage. In case of microcantilever an accurate modelling
includes the effect of the initial curvature due to microfabrication. In double
clamped microbeams a preloading applied by tensile stress is considered.
Geometrical onlinearity caused by mechanical coupling between axial and
flexural behaviour is detected and modelled. Experimental results demonstrate a
good agreement between FEM approaches proposed and tests. A fairly fast and
accurate prediction of pull-in condition is performed, thus numerical models
can be used to identify residual stress in microbridges by reverse analysis
from the measured value of pull-in voltage.


title:
Validation of compact models of microcantilever actuators for RF-MEMS
  application

abstract:
  Microcantilever specimens for in-plane and out-ofplane bending tests are here
analyzed. Experimental validation of 2D and 3D numerical models is performed.
Main features of in-plane and out-of-plane layouts are then discussed.
Effectiveness of plane models to predict pull-in in presence of geometric
nonlinearity due to a large tip displacement and initial curvature of microbeam
is investigated. The paper is aimed to discuss the capability of 2D models to
be used as compact tools to substitute some model order reduction techniques,
which appear unsuitable in presence of both electromechanical and geometric
nonlinearities.


title:
Numerical Investigation of Laser-Assisted Nanoimprinting on a Copper
  Substrate from a Perspective of Heat Transfer Analysis

abstract:
  The technique of laser-assisted nanoimprinting lithography (LAN) has been
proposed to utilize an excimer laser to irradiate through a quartz mold and
melts a thin polymer film on the substrate for micro- to nano-scaled
fabrications. In the present study, the novel concept of that copper was
adopted as the substrate instead of silicon, which is conventionally used, was
proposed. The micro/nano structures on the copper substrate could be fabricated
by chemical/electrochemical etching or electroforming ; following by the
patterns have been transferred onto the substrate using LAN process.
Alternatives of the substrate materials could lead versatile applications in
micro/nano-fabrication. To demonstrate the feasibility of this concept
numerically, this study introduced optical multiple reflection theory to
perform both analytical and numerical modeling during the process and to
predict the thermal response theoretically.


title: Micro-electroforming metallic bipolar electrodes for mini-DMFC stacks

abstract:
  This paper describes the development of metallic bipolar plate fabrication
using micro-electroforming process for mini-DMFC (direct methanol fuel cell)
stacks. Ultraviolet (UV) lithography was used to define micro-fluidic channels
using a photomask and exposure process. Micro-fluidic channels mold with 300
micrometers thick and 500 micrometers wide were firstly fabricated in a
negative photoresist onto a stainless steel plate. Copper micro-electroforming
was used to replicate the micro-fluidic channels mold. Following by sputtering
silver (Ag) with 1.2 micrometers thick, the metallic bipolar plates were
completed. The silver layer is used for corrosive resistance. The completed
mini-DMFC stack is a 2x2 cm2 fuel cell stack including a 1.5x1.5 cm2 MEA
(membrane electrode assembly). Several MEAs were assembly into mini-DMFC stacks
using the completed metallic bipolar plates. All test results showed the
metallic bipolar plates suitable for mini-DMFC stacks. The maximum output power
density is 9.3mW/cm2 and current density is 100 mA/cm2 when using 8 vol. %
methanol as fuel and operated at temperature 30 degrees C. The output power
result is similar to other reports by using conventional graphite bipolar
plates. However, conventional graphite bipolar plates have certain difficulty
to be machined to such micro-fluidic channels. The proposed
micro-electroforming metallic bipolar plates are feasible to miniaturize DMFC
stacks for further portable 3C applications.


title:
On the determination of Poisson's ratio of stressed monolayer and
  bilayer submicron thick films

abstract:
  In this paper, the bulge test is used to determine the mechanical properties
of very thin dielectric membranes. Commonly, this experimental method permits
to determine the residual stress (s0) and biaxial Young's modulus (E/(1-u)).
Associating square and rectangular membranes with different length to width
ratios, the Poisson's ratio (u) can also be determined. LPCVD Si3N4 monolayer
and Si3N4/SiO2 bilayer membranes, with thicknesses down to 100 nm, have been
characterized giving results in agreement with literature for Si3N4, E = 212
$\pm$ 14 GPa, s0 = 420 $\pm$ 8 and u = 0.29.


title:
New high fill-factor triangular micro-lens array fabrication method
  using UV proximity printing

abstract:
  A simple and effective method to fabricate a high fill-factor triangular
microlens array using the proximity printing in lithography process is
reported. The technology utilizes the UV proximity printing by controlling a
printing gap between the mask and substrate. The designed approximate triangle
microlens array pattern can be fabricated the high fill-factor triangular
microlens array in photoresist. It is due to the UV light diffraction to
deflect away from the aperture edges and produce a certain exposure in
photoresist material outside the aperture edges. This method can precisely
control the geometric profile of high fill factor triangular microlens array.
The experimental results showed that the triangular micro-lens array in
photoresist could be formed automatically when the printing gap ranged from 240
micrometers to 840 micrometers. The gapless triangular microlens array will be
used to increases of luminance for backlight module of liquid crystal displays.


title:
Design Optimization for an Electro-Thermally Actuated Polymeric
  Microgripper

abstract:
  Thermal micro-actuators are a promising solution to the need for
large-displacement, gentle handling force, low-power MEMS actuators. Potential
applications of these devices are micro-relays, assembling and miniature
medical instrumentation. In this paper the development of thermal
microactuators based on SU-8 polymer is described. The paper presents the
development of a new microgripper which can realize a movement of the gripping
arms with possibility for positioning and manipulating of the gripped object.
Two models of polymeric microgripper electrothermo- mechanical actuated, using
low actuation voltages, designed for SU-8 polymer fabrication were presented.
The electro-thermal microgrippers were designed and optimized using finite
element simulations. Electro-thermo-mechanical simulations based on finite
element method were performed for each of the model in order to compare the
results. Preliminary experimental tests were carried out.


title: Concentration of measure via approximated Brunn--Minkowski inequalities

abstract:
  We prove that an approximated version of the Brunn--Minkowski inequality with
volume distortion coefficient implies a Gaussian concentration-of-measure
phenomenon. Our main theorem is applicable to discrete spaces.


title:
Design And Fabrication of High Numerical Aperture And Low Aberration
  Bi-Convex Micro Lens Array

abstract:
  Micro lens array is crucial in various kinds of optical and electronic
applications. A micro lens array with high numerical aperture (NA) and low
aberration is in particular needed. This research is aimed to design and
fabricate such a micro lens array with simple structure while keeps the same NA
of a same-diameter hemisphere lens. A bi-convex semispherical micro lens array,
with corresponding NA 0.379, by PDMS is first designed and analyzed.
Experiments are further conducted to fabricate the designed micro lens array by
the thermal reflow process. The formed profile is then sputtered with copper to
serve as the mold. The front and the rear micro lens array are fabricated by
plating PDMS to the mold and then assembled to form the designed micro lens
array.


title: Micromachined Inclinometer Based on Fluid Convection

abstract:
  This paper presents a numerical simulation and experimental results of a
one-dimensional thermal inclinometer with the cavity filled of gas and liquid.
The sensor principle consists of one heating resistor placed between two
detectors. When the resistor is electrically powered, it creates a symmetrical
temperature profile inside a micromachined silicon cavity. By applying a tilt
to the sensor, the profile shifts in the same direction of the sensible axis
corresponding to the horizontal one to one. The temperature profile and the
sensitivity according to the CO2 gas and mineral oil SAE50 have been studied
using numerical resolution of fluid dynamics equations with the computational
fluid dynamics (CFD) software package Fluent V6.2. We have shown that the
sensitivity of liquid sensors is higher than the gas sensors one. By using
micromachined silicon technique, a thermal inclinometer with one pair of
detectors placed at 300 um from the heater has been made. Experimental
measurements corroborate with the numerical simulation.


title:
Model Based Sensor System for Temperature Measurement in R744 Air
  Conditioning Systems

abstract:
  The goal is the development of a novel principle for the temperature
acquisition of refrigerants in CO2 air conditioning systems. The new approach
is based on measuring the temperature inside a pressure sensor, which is also
needed in the system. On the basis of simulative investigations of different
mounting conditions functional relations between measured and medium
temperature will be derived.


title:
Integrated 3D Sound Intensity Sensor with Four-Wire Particle Velocity
  Sensors

abstract:
  A new symmetrical four-wire sensor configuration has resulted in a fully
integrated sound intensity sensor with significant lower noise floor and
smaller size than its predecessors. An integrated sound pressure sensor was
further miniaturized by using a folded "back chamber" at both sides of the
chip.


title:
High Aspect Pattern Formation by Integration of Micro Inkjetting and
  Electroless Plating

abstract:
  This paper reports on formation of high aspect micro patterns on low
temperature co-fired ceramic (LTCC) substrates by integrating micro inkjetting
with electroless plating. Micro inkjetting was realized by using an inkjetting
printer that ejects ink droplets from a printhead. This printhead consists of a
glass nozzle with a diameter of 50 micrometers and a piezoelectric transducer
that is coated on the nozzle. The silver colloidal solution was inkjetted on a
sintered CT800 ceramic substrate, followed by curing at 200 degrees C for 60
minutes. As a result, the silver trace with a thickness of 200 nm was obtained.
The substrate, with the ejected silver thin film as the seed layer, was then
immersed into a preinitiator solution to coat a layer of palladium for
enhancing the deposition of nickel. Electroless nickel plating was successfully
conducted at a rate of 0.39 micrometers /min, and the thickness of traces was
plated up to 84 micrometers. This study demonstrates that the integration of
inkjetting with plating is an effective method to form high aspect patterns at
the demand location.


title: A Nanostructual Microwave Probe Used for Atomic Force Microscope

abstract:
  In order to develop a new structure microwave probe, the fabrication of AFM
probe on the GaAs wafer was studied. A waveguide was introduced by evaporating
Au film on the top and bottom surfaces of the GaAs AFM probe. A tip having 8
micrometers high, and curvature radius about 50 nm was formed. The dimensions
of the cantilever are 250x30x15 micrometers. The open structure of the
waveguide at the tip of the probe was introduced by using FIB fabrication. AFM
topography of a grating sample was measured by using the fabricated GaAs
microwave probe. The fabricated probe was found having nanometer scale
resolution, and microwave emission was detected successfully at the tip of the
probe by approaching Cr-V steel and Au wire samples.


title:
SANA - Security Analysis in Internet Traffic through Artificial Immune
  Systems

abstract:
  The Attacks done by Viruses, Worms, Hackers, etc. are a Network
Security-Problem in many Organisations. Current Intrusion Detection Systems
have significant Disadvantages, e.g. the need of plenty of Computational Power
or the Local Installation. Therefore, we introduce a novel Framework for
Network Security which is called SANA. SANA contains an artificial Immune
System with artificial Cells which perform certain Tasks in order to to support
existing systems to better secure the Network against Intrusions. The
Advantages of SANA are that it is efficient, adaptive, autonomous, and
massively-distributed. In this Article, we describe the Architecture of the
artificial Immune System and the Functionality of the Components. We explain
briefly the Implementation and discuss Results.


title: Lyapunov control of a quantum particle in a decaying potential

abstract:
  A Lyapunov-based approach for the trajectory generation of an $N$-dimensional
Schr{\"o}dinger equation in whole $\RR^N$ is proposed. For the case of a
quantum particle in an $N$-dimensional decaying potential the convergence is
precisely analyzed. The free system admitting a mixed spectrum, the dispersion
through the absolutely continuous part is the main obstacle to ensure such a
stabilization result. Whenever, the system is completely initialized in the
discrete part of the spectrum, a Lyapunov strategy encoding both the distance
with respect to the target state and the penalization of the passage through
the continuous part of the spectrum, ensures the approximate stabilization.


title: High Density out-of-Plane Microprobe Array

abstract:
  MEMS technology has been developed rapidly in the last few years. More and
more special micro structures were discussed in several publications. However,
all of the structures were produced by consist of the three fundamental
structures, which included bridge, cantilever and membrane structures. Even the
more complex structures were no exception. The cantilever with the property of
simple design and easy fabrication among three kinds of fundamental structure,
therefore, it was popular used in the design of MEMS device.


title:
Simulation of Coating -Visco-Elastic liquid in the Mico-Nip of Metering
  Size Press

abstract:
  For a set of operating conditions and coating color formulations, undesirable
phenomena like color spitting and coating ribs may be triggered in the
Micro-nip during the coating process. Therefore, our interest in this work
focus on another parameter affect on the undesirable phenomena as the vortices
in the Micro-nip. The problem deals with the flow through the Micro-nip of
metering size press. The flow enters and exits at a tangential velocity of 20
m/s between two rollers with diameter 80 cm and 60 -m apart. In the upper and
bottom part of the domain the angular velocity is 314 rad /s. It has one
sub-domain. Previous studies focus on the Micro-nip without considering the
inertia and the viscoelasticity of the material. Roll coating is a technique
commonly used in the coating industry to meter a thin fluid film on a moving
substrate. During the film formation, the fluid is subjected to very high shear
and extensional rates over a very short period of time. The fluid domain
changes as a function of the hydrodynamic pressure within the nip as a result
of the deformable cover usually used on one of the rolls. The free surface also
adds more complexity to the flow due to the force equilibrium in the fluid gas
interface. Last of all, the rheological behavior of the coating fluid is
usually non-Newtonian, so the metering flow hydrodynamics is finally very
difficult to describe. It is concluded that the normal forces of micro-nip
increases with increasing the inhibitors. Therefore, it affects on the
smoothness and creates defects. On the other hand, it can be concluded that the
creation of big vortex in the middle of micro-nip affects on the coating liquid
behavior.


title:
A Microcantilever-based Gas Flow Sensor for Flow Rate and Direction
  Detection

abstract:
  The purpose of this paper is to apply characteristics of residual stress that
causes cantilever beams to bend for manufacturing a micro-structured gas flow
sensor. This study uses a silicon wafer deposited silicon nitride layers,
reassembled the gas flow sensor with four cantilever beams that perpendicular
to each other and manufactured piezoresistive structure on each
micro-cantilever by MEMS technologies, respectively. When the cantilever beams
are formed after etching the silicon wafer, it bends up a little due to the
released residual stress induced in the previous fabrication process. As air
flows through the sensor upstream and downstream beam deformation was made,
thus the airflow direction can be determined through comparing the resistance
variation between different cantilever beams. The flow rate can also be
measured by calculating the total resistance variations on the four
cantilevers.


title:
Process nano scale mechanical properties measurement of thin metal films
  using a novel paddle cantilever test structure

abstract:
  A new technique was developed for studying the mechanical behavior of
nano-scale thin metal films on substrate is presented. The test structure was
designed on a novel "paddle" cantilever beam specimens with dimensions as few
hundred nanometers to less than 10 nanometers. This beam is in triangle shape
in order to provide uniform plane strain distribution. Standard clean room
processing was used to prepare the paddle sample. The experiment can be
operated by using the electrostatic deflection on the paddle uniform
distributed stress cantilever beam and then measure the deposited thin metal
film materials on top of it. A capacitance technique was used to measurement on
the other side of the deflected plate to measure its deflection with respect to
the force. The measured strain was converted through the capacitance
measurement for the deflection of the cantilever. System performance on the
residual stress measurement of thin films are calculated with three different
forces on the "paddle" cantilever beam, including the force due to the film,
compliance force and electrostatic force.


title: High Q-factor CMOS-MEMS inductor

abstract:
  This study investigates a high Q-factor spiral inductor fabricated by the
CMOS (complementary metal oxide semiconductor) process and a post-process. The
spiral inductor is manufactured on silicon substrate using the 0.35 micrometers
CMOS process. In order to reduce the substrate loss and enhance the Q-factor of
the inductor, silicon substrate under the inductor is removed using a
post-process. The post-process uses RIE (reactive ion etching) to etch the
sacrificial layer of silicon dioxide, and then TMAH (tetra methyl ammonium
hydroxide) is employed to remove the underlying silicon substrate and obtain
the suspended spiral inductor. The advantage of the post process is compatible
with the CMOS process. The Agilent 8510C network analyzer and a Cascade probe
station are used to measure the performances of the spiral inductor.
Experiments indicate that the spiral inductor has a Q-factor of 15 at 11 GHz,
an inductance of 4 nH at 25.5 GHz and a self-resonance frequency of about 27
GHz.


title: Copper Electrodeposition for 3D Integration

abstract:
  Two dimensional (2D) integration has been the traditional approach for IC
integration. Due to increasing demands for providing electronic devices with
superior performance and functionality in more efficient and compact packages,
has driven the semiconductor industry to develop more advanced packaging
technologies. Three-dimensional (3D) approaches address both miniaturization
and integration required for advanced and portable electronic products.
Vertical integration proved to be essential in achieving a greater integration
flexibility of disparate technologies, reason for which a general trend of
transition from 2D to 3D integration is currently being observed in the
industry. 3D chip integration using through silicon via (TSV) copper is
considered one of the most advanced technologies among all different types of
3D packaging technologies. Copper electrodeposition is one of technologies that
enable the formation of TSV structures. Because of its well-known application
for copper damascene, it was believed that its transfer to filling TSV vias
would be easily adopted. However, as any new technology at its beginning, there
are several challenges that need to be addressed and resolved before becoming a
fully mature technology. This paper will address the TSV fill processes using
copper electrodeposition, the advantages as well as difficulties associated
with this technology and approaches taken to overcome them. Electrochemical
characterization of the organics behavior and their effect on via filling will
be presented. The effect of wafer design on process performance and throughput,
including necessary process optimizations that are required for achieving
void-free via filling while reducing the processing time, will be discussed.


title: Technologies for 3D Heterogeneous Integration

abstract:
  3D-Integration is a promising technology towards higher interconnect
densities and shorter wiring lengths between multiple chip stacks, thus
achieving a very high performance level combined with low power consumption.
This technology also offers the possibility to build up systems with high
complexity just by combining devices of different technologies. For ultra thin
silicon is the base of this integration technology, the fundamental processing
steps will be described, as well as appropriate handling concepts. Three main
concepts for 3D integration have been developed at IZM. The approach with the
greatest flexibility called Inter Chip Via - Solid Liquid Interdiffusion
(ICV-SLID) is introduced. This is a chip-to-wafer stacking technology which
combines the advantages of the Inter Chip Via (ICV) process and the
solid-liquid-interdiffusion technique (SLID) of copper and tin. The fully
modular ICV-SLID concept allows the formation of multiple device stacks. A test
chip was designed and the total process sequence of the ICV-SLID technology for
the realization of a three-layer chip-to-wafer stack was demonstrated. The
proposed wafer-level 3D integration concept has the potential for low cost
fabrication of multi-layer high-performance 3D-SoCs and is well suited as a
replacement for embedded technologies based on monolithic integration. To
address yield issues a wafer-level chip-scale handling is presented as well, to
select known-good dies and work on them with wafer-level process sequences
before joining them to integrated stacks.


title: Through Silicon Vias as Enablers for 3D Systems

abstract:
  This special session on 3D TSV's will highlight some of the fabrication
processes and used technologies to create vias from the frontside of an active
circuit to its backside and potential implementation solutions to form complex
systems leveraging these novel possibilities. General techniques for via
formation are discussed as well as advanced integration solutions leveraging
the power of 3D TSV's.


title: Fabrication of 3D Packaging TSV using DRIE

abstract:
  Emerging 3D chips stacking and MEMS/Sensors packaging technologies are using
DRIE (Deep Reactive Ion Etching) to etch through-silicon via (TSV) for advanced
interconnections. The interconnection step can be done prior to or post CMOS
manufacturing, each requiring different etch process performances. A review of
the DRIE capability in terms of etching profile, etch rate, etch depth has been
carried out. Excellent tool flexibility allows a wide range of basic and
complex profiles to be achieved. Unlike other techniques, DRIE has the
capability to etch feature sizes ranging from sub-micron to millimeter width.
The main specificity of the DRIE is that etch rate is sensitive to the total
exposed area and the aspect ratio. For the TSV applications, where the total
exposed area is lower than 10%, high etch rates are achievable. A study has
also been done to highlight the importance of via profile for the success of
the refilling step. In addition, due to the high flexibility of DRIE, we also
explore the capability of using this technique for wafer thinning and plasma
die separation.


title:
Study of First-Order Thermal Sigma-Delta Architecture for Convective
  Accelerometers

abstract:
  This paper presents the study of an original closed-loop conditioning
approach for fully-integrated convective inertial sensors. The method is
applied to an accelerometer manufactured on a standard CMOS technology using an
auto-aligned bulk etching step. Using the thermal behavior of the sensor as a
summing function, a first order sigma-delta modulator is built. This
"electro-physical" modulator realizes an analog-to-digital conversion of the
signal. Besides the feedback scheme should improve the sensor performance.


title:
Tunable stress and controlled thickness modification in graphene by
  annealing

abstract:
  Graphene has many unique properties which make it an attractive material for
fundamental study as well as for potential applications. In this paper, we
report the first experimental study of process-induced defects and stress in
graphene using Raman spectroscopy and imaging. While defects lead to the
observation of defect-related Raman bands, stress causes shift in phonon
frequency. A compressive stress (as high as 2.1 GPa) was induced in graphene by
depositing a 5 nm SiO2 followed by annealing, whereas a tensile stress (~ 0.7
GPa) was obtained by depositing a thin silicon capping layer. In the former
case, both the magnitude of the compressive stress and number of graphene
layers can be controlled or modified by the annealing temperature. As both the
stress and thickness affect the physical properties of graphene, this study may
open up the possibility of utilizing thickness and stress engineering to
improve the performance of graphene-based devices. Local heating techniques may
be used to either induce the stress or reduce the thickness selectively.


title: High Density Through Silicon Via (TSV)

abstract:
  The Through Silicon Via (TSV) process developed by Silex provides down to 30
micrometers pitch for through wafer connections in up to 600 micrometers thick
substrates. Integrated with MEMS designs it enables significantly reduced die
size and true "Wafer Level Packaging" - features that are particularly
important in consumer market applications. The TSV technology also enables
integration of advanced interconnect functions in optical MEMS, sensors and
microfluidic devices. In addition the Via technology opens for very interesting
possibilities considering integration with CMOS processing. With several
companies using the process already today, qualified volume manufacturing in
place and a line-up of potential users, the process is becoming a standard in
the MEMS industry. We provide a introduction to the via formation process and
also present some on the novel solutions made available by the technology.


title:
Pairing symmetry and properties of iron-based high temperature
  superconductors

abstract:
  Pairing symmetry is important to indentify the pairing mechanism. The
analysis becomes particularly timely and important for the newly discovered
iron-based multi-orbital superconductors. From group theory point of view we
classified all pairing matrices (in the orbital space) that carry irreducible
representations of the system. The quasiparticle gap falls into three
categories: full, nodal and gapless. The nodal-gap states show conventional
Volovik effect even for on-site pairing. The gapless states are odd in orbital
space, have a negative superfluid density and are therefore unstable. In
connection to experiments we proposed possible pairing states and implications
for the pairing mechanism.


title: Complex Network view of performance and risks on Airport Networks

abstract:
  Air transportation has been becoming a major part of transportation
infrastructure worldwide. Hence the study of the Airports Networks, the
backbone of air transportation, is becoming increasingly important. In complex
systems domain, airport networks are modeled as graphs (networks) comprising of
airports (vertices or nodes) that are linked by flight connectivities among the
airports. A complex network analysis of such a model offers holistic insight
about the performance and risks in such a network. We review the performance
and risks of networks with the help of studies that have been done on some of
the airport networks. We present various network parameters those could be
potentially used as a measure of performance and risks on airport networks. We
will also see how various risks, such as break down of airports, spread of
diseases across the airport network could be assessed based on the network
parameters. Further we review how these insights could possibly be used to
shape more efficient and safer airport networks.


title:
Rejection of Power Supply Noise in Wheatstone Bridges : Application to
  Piezoresistive MEMS

abstract:
  This paper deals with the design of MEMS using piezoresistivity as
transduction principle. It is demonstrated that when the sensor topology
doesn't allow a perfect matching of strain gauges, the resolution is limited by
the ability of the conditioning circuit (typically a Wheatstone bridge) to
reject power supply noise. As this ability is strongly reduced when an offset
voltage is present at the output of the bridge, the proposed architecture
implements a feedback loop to control MOS transistors inserted in the
Wheatstone bridge to compensate resistor mismatches. This feedback exhibits a
very good offset cancellation and therefore a better resolution is achieved.


title: Next Generation of TCAD Environments for MEMS Design

abstract:
  In this paper we present the latest version of the TCAD environment BICEP'S
(Braunschweigs Integrated CAD-Environment for Product Planning and Process
Simulation). By using a central process database, which allows the exchange of
all relevant process data it is able to overcome many of the mentioned
obstacles. The database and process planning tool can be used by process
developers to document changes in process settings and the influence of such
changes on the process result. This information can then be used by the
designers to set-up a simulation file for a detailed analysis of the impact of
such parameter changes on the requested design. This will be shown by the
example of silicon etching using an atomistic etch simulator.


title: Noise Analysis and Noise-based Optimization for Resonant MEMS Structures

abstract:
  This paper presents a detailed noise analysis and a noise-based optimization
procedure for resonant MEMS structures. A design for high sensitivity of MEMS
structures needs to take into account the noise shaping induced by damping
phenomena at micro scale. The existing literature presents detailed models for
the damping at microscale, but usually neglects them in the noise analysis
process, assuming instead a white spectrum approximation for the
mechano-thermal noise. The present work extends the implications of the complex
gas-solid interaction into the field of noise analysis for mechanical sensors,
and provides a semi-automatic procedure for behavioral macromodel extraction
and sensor optimization with respect to signal-to-noise ratio.


title:
Exact relativistic kinetic theory of an electron beam-plasma system:
  hierarchy of the competing modes in the system parameter space

abstract:
  Besides being one of the most fundamental basic issues of plasma physics, the
stability analysis of an electron beam-plasma system is of critical relevance
in many areas of physics. Surprisingly, decades of extensive investigation had
not yet resulted in a realistic unified picture of the multidimensional
unstable spectrum within a fully relativistic and kinetic framework. All
attempts made so far in this direction were indeed restricted to simplistic
distribution functions and/or did not aim at a complete mapping of the
beam-plasma parameter space. The present paper comprehensively tackles this
problem by implementing an exact linear model. We show that three kinds of
modes compete in the linear phase, which can be classified according to the
direction of their wavenumber with respect to the beam. We then determine their
respective domain of preponderance in a three-dimensional parameter space. All
these results are supported by multidimensional particle-in-cell simulations.


title:
Haptic sensing for MEMS with application for cantilever and Casimir
  effect

abstract:
  This paper presents an implementation of the Cosserat theory into haptic
sensing technologies for real-time simulation of microstructures. Cosserat
theory is chosen instead of the classical theory of elasticity for a better
representation of stress, especially in the nonlinear regime. The use of
Cosserat theory leads to a reduction of the complexity of the modelling and
thus increases its capability for real time simulation which is indispensable
for haptic technologies. The incorporation of Cosserat theory into haptic
sensing technology enables the designer to simulate in real-time the components
in a virtual reality environment (VRE) which can enable virtual manufacturing
and prototyping. The software tool created as a result of this methodology
demonstrates the feasibility of the proposed model. As test demonstrators, a
cantilever microbeam and microbridge undergoing bending in VRE are presented.


title: On-Chip Hotplate for Temperature Control of Cmos Saw Resonators

abstract:
  Due to the sensitivity of the piezoelectric layer in surface acoustic wave
(SAW) resonators to temperature, a method of achieving device stability as a
function of temperature is required. This work presents the design, modeling
and characterization of integrated dual-serpentine polysilicon resistors as a
method for temperature control of CMOS SAW resonators. The design employs the
oven control temperature stabilization scheme where the device's temperature is
elevated to higher than Tmax to maintain constant device temperature. The
efficiency of the polysilicon resistor as a heating element was verified
through a 1-D partial differential equation model, 3-D CoventorWare finite
element simulations and measurements using Compix thermal camera. To verify
that the on-chip hotplate is effective as a temperature control method, both DC
and RF measurements of the heater together with the resonator were conducted.
Experimental results have indicated that the TCF of the CMOS SAW resonator of
-97.2 ppm/deg C has been reduced to -23.19 ppm/deg C when heated to 56 deg C.


title: Modelling methodology of MEMS structures based on Cosserat theory

abstract:
  Modelling MEMS involves a variety of software tools that deal with the
analysis of complex geometrical structures and the assessment of various
interactions among different energy domains and components. Moreover, the MEMS
market is growing very fast, but surprisingly, there is a paucity of modelling
and simulation methodology for precise performance verification of MEMS
products in the nonlinear regime. For that reason, an efficient and rapid
modelling approach is proposed that meets the linear and nonlinear dynamic
behaviour of MEMS systems.


title:
Low Voltage Totally Free Flexible RF MEMS Switch With Anti-Stiction
  System

abstract:
  This paper concerns a new design of RF MEMS switch combined with an
innovative process which enable low actuation voltage (<5V) and avoid stiction.
First, the structure described with principal design issues, the corresponding
anti-stiction system is presented and FEM simulations are done. Then, a short
description of the process flow based on two non polymer sacrificial layers.
Finally, RF measurements are presented and preliminary experimental protocol
and results of anti-stiction validation is detailed. Resulting RF performances
are -30dB of isolation and -0.45dB of insertion loss at 10 GHz.


title:
High Quality Factor Silicon Cantilever Driven by PZT Actuator for
  Resonant Based Mass Detection

abstract:
  A high quality factor (Q-factor) piezoelectric lead zirconat titanate (PZT)
actuated single crystal silicon cantilever was proposed in this paper for
resonant based ultra-sensitive mass detection. Energy dissipation from
intrinsic mechanical loss of the PZT film was successfully compressed by
separating the PZT actuator from resonant structure. Excellent Q-factor, which
is several times larger than conventional PZT cantilever, was achieved under
both atmospheric pressure and reduced pressures. For a 30 micrometer-wide 100
micrometer-long cantilever, Q-factor was measured as high as 1113 and 7279
under the pressure of 101.2 KPa and 35 Pa, respectively. Moreover, it was found
that high-mode vibration can be realized by the cantilever for the pursuit of
great Q-factor, while support loss became significant because of the increased
vibration amplitude at the actuation point. An optimized structure using
node-point actuation was suggested then to suppress corresponding energy
dissipation.


title:
A New Four States High Deflection Low Actuation Voltage Electrostatic
  Mems Switch for RF Applications

abstract:
  This paper presents a new electrostatic MEMS (MicroElectroMechanical System)
based on a single high reliability totally free flexible membrane. Using four
electrodes, this structure enables four states which allowed large deflections
(4$\mu$m) with low actuation voltage (7,5V). This design presents also a good
contact force and improve the restoring force of the structure. As an example
of application, a Single Pole Double Throw (SPDT) for 24GHz applications, based
on this design, has been simulated.


title: Design and Fabrication of a Novel Micro Electromagnetic Actuator

abstract:
  The present study presents a new micro electromagnetic actuator utilizing a
PDMS membrane with a magnet. The actuator is integrated with micro coils to
electromagnetically actuate the membrane and results in a large deflection. The
micro electromagnetic actuator proposed in this study is easily fabricated and
is readily integrated with existing bio-medical chips due to its planar
structure.


title: On the inverse scattering of star-shape LC-networks

abstract:
  The study of the scattering data for a star-shape network of LC-transmission
lines is transformed into the scattering analysis of a Schr\"odinger operator
on the same graph. The boundary conditions coming from the Kirchhoff rules
ensure the existence of a unique self-adjoint extension of the mentioned
Schr\"odinger operator. While the graph consists of a number of infinite
branches and a number finite ones, all joining at a central node, we provide a
construction of the scattering solutions. Under non-degenerate circumstances
(different wave travelling times for finite branches), we show that the study
of the reflection coefficient in the high-frequency regime must provide us with
the number of the infinite branches as well as the the wave travelling times
for finite ones.


title: Flexible Micro Thermoelectric Generator based on Electroplated Bi2Te3

abstract:
  We present and discuss the fabrication process and the performance of a
flexible micro thermoelectric generator with electroplated Bi2Te3 thermocouples
in a SU-8 mold. Demonstrator devices generate 278uWcm-2 at dTmeas=40K across
the experimental set up. Based on model calculations, a temperature difference
of dTG=21.4K across the generator is assumed. Due to the flexible design and
the chosen generator materials, the performance stays high even for curved
contact surfaces. The measurement results correlate well with the model based
design optimization predictions.


title:
A Novel Piezoelectric Microtransformer for Autonmous Sensors
  Applications

abstract:
  This work relates to a novel piezoelectric transformer to be used in an
autonomous sensor unit, possibly in conjunction with a RF-MEMS retro-modulator.


title:
Optimization of efficiency and energy density of passive micro fuel
  cells and galvanic hydrogen generators

abstract:
  A PEM micro fuel cell system is described which is based on self-breathing
PEM micro fuel cells in the power range between 1 mW and 1W. Hydrogen is
supplied with on-demand hydrogen production with help of a galvanic cell, that
produces hydrogen when Zn reacts with water. The system can be used as a
battery replacement for low power applications and has the potential to improve
the run time of autonomous systems. The efficiency has been investigated as
function of fuel cell construction and tested for several load profiles.


title:
Design and Fabrication of Acoustic Wave Actuated Microgenerator for
  Portable Electronic Devices

abstract:
  The past few years have seen an increasing focus on energy harvesting issue,
including power supply for portable electric devices. Utilize scavenging
ambient energy from the environment could eliminate the need for batteries and
increase portable device lifetimes indefinitely. In addition, through MEMS
technology fabricated micro-generator could easy integrate with these small or
portable devices. Several different ambient sources, including solar, vibration
and temperature effect, have already exploited [1-3]. Each energy source should
be used in suitable environment, therefore to produce maximum efficiency. In
this paper, we present an acoustic wave actuated micro-generator for power
system by using the energy of acoustic waves, such as the sound from human
voices or speakerphone, to actuate a MEMS-type electromagnetic transducer. This
provides a longer device lifetime and greater power system convenience.
Moreover, it is convenient to integrate MEMS-based microgenerators with small
or porta le devices


title: Package Hermeticity Testing with Thermal Transient Measurements

abstract:
  The rapid incursion of new technologies such as MEMS and smart sensor device
manufacturing requires new tailor-made packaging designs. In many applications
these devices are exposed to humid environments. Since the penetration of
moisture into the package may result in internal corrosion or shift of the
operating parameters, the reliability testing of hermetically sealed packages
has become a crucial question in the semiconductor industry.


title:
Micro-tensile tests on micromachined metal on polymer specimens:
  elasticity, plasticity and rupture

abstract:
  This study is focused on the mechanical characterization of materials used in
microelectronic and micro- electromechanical systems (MEMS) devices. In order
to determine their mechanical parameters, a new deformation bench test with
suitable micromachined specimens have been developed. Uniaxial tensile tests
were performed on "low cost" specimens, consisting in electroplated thin copper
films and structures, deposited on a polimide type substrate. Moreover, a
cyclic mechanical actuation via piezoelectric actuators was tested on the same
deformation bench. These experiments validate the device for performing dynamic
characterization of materials, and reliability studies of different
microstructures.


title: Open Ended Microwave Oven for Packaging

abstract:
  A novel open waveguide cavity resonator is presented for the combined
variable frequency microwave curing of bumps, underfills and encapsulants, as
well as the alignment of devices for fast flip-chip assembly, direct chip
attach (DCA) or wafer-scale level packaging (WSLP). This technology achieves
radio frequency (RF) curing of adhesives used in microelectronics,
optoelectronics and medical devices with potential simultaneous micron-scale
alignment accuracy and bonding of devices. In principle, the open oven cavity
can be fitted directly onto a flip-chip or wafer scale bonder and, as such,
will allow for the bonding of devices through localised heating thus reducing
the risk to thermally sensitive devices. Variable frequency microwave (VFM)
heating and curing of an idealised polymer load is numerically simulated using
a multi-physics approach. Electro-magnetic fields within a novel open ended
microwave oven developed for use in micro-electronics manufacturing
applications are solved using a de icated Yee scheme finite-difference
time-domain (FDTD) solver. Temperature distribution, degree of cure and thermal
stresses are analysed using an Unstructured Finite Volume method (UFVM)
multi-physics package. The polymer load was meshed for thermophysical analysis,
whilst the microwave cavity - encompassing the polymer load - was meshed for
microwave irradiation. The two solution domains are linked using a
cross-mapping routine. The principle of heating using the evanescent fringing
fields within the open-end of the cavity is demonstrated. A closed loop
feedback routine is established allowing the temperature within a lossy sample
to be controlled. A distribution of the temperature within the lossy sample is
obtained by using a thermal imaging camera.


title: On the dynamics and thermodynamics of small Markov-type material systems

abstract:
  The collective properties of small material systems considered as
semidynamical systems revealing the Markov-type irreversible evolution, are
investigated. It is shown that these material systems admit their treatment as
thermodynamic systems in diathermal and isothermal conditions. A kinetic
equation describing statistical regularities of the Markov-type material
systems and constrained by the compatibility condition with the first and
second laws of thermodynamics and with the relaxation postulate, is proposed.
The influence of external parameters on the Gibbs distribution of small
material systems is discussed.


title: Mechanical Fatigue on Gold MEMS Devices: Experimental Results

abstract:
  The effect of mechanical fatigue on structural performances of gold devices
is investigated. The pull-in voltage of special testing micro-systems is
monitored during the cyclical load application. The mechanical collapse is
identified as a dramatic loss of mechanical strength of the specimen. The
fatigue limit is estimated through the stair-case method by means of the
pull-in voltage measurements. Measurements are performed by means of the
optical interferometric technique.


title: Lifetime statistics in transitional pipe flow

abstract:
  Several experimental and numerical studies have shown that turbulent motions
in circular pipe flow near transitional Reynolds numbers may not persist
forever, but may decay. We study the properties of these decaying states within
direct numerical simulations for Reynolds numbers up to 2200 and in pipes with
lengths equal to 5, 9 and 15 times the diameter. We show that the choice of the
ensemble of initial conditions affects the short time parts of lifetime
distributions, but does not change the characteristic decay rate for long
times. Comparing lifetimes for pipes of different length we notice a linear
increase in the characteristic lifetime with length, which reproduces the
experimental results when extrapolated to 30 diameters, the length of an
equilibrium turbulent puff at these Reynolds numbers.


title:
Comment on "Interference in the Collective Electron Momentum in Double
  Photoionization of H2"

abstract:
  We give supporting evidence for and elaborate further on the fact -see Kreidi
et al., Phys. Rev. Lett. 100, 133005 (2008)- that ionic states are essential
for covalent dihydrogen H2.


title: Electromagnetic radiation from a laser wakefield accelerator

abstract:
  Coherent and incoherent electromagnetic radiation emitted from a laser
wakefield accelerator is calculated based on Lienard-Wiechert potentials. It is
found that at wavelengths longer than the bunch length, the radiation is
coherent. The coherent radiation, which typically lies in the infrared range,
shows features that reveal details of the acceleration process and properties
of the electron bunch, such as its duration, charge, energy, and offset with
respect to the wakefield axis. The incoherent range of the spectrum, which
extends to the X-ray frequency range, consists of rather broad peaks, which are
caused by the acceleration.


title: Structure and Stability of Two-Dimensional Complexes of C_20 Fullerenes

abstract:
  Two-dimensional complexes of C_20 fullerenes connected to each other by
covalent bonds have been studied. Several isomers with different types of
intercluster bonds have been revealed. The lifetimes of the (C_20)_MxM systems
with M = 2 and 3 have been directly calculated at T = 1800 - 3300 K making use
of molecular dynamics. It has been shown that these complexes lose their
periodic cluster structure due to either coalescence of two fullerenes C_20 or
decay of C_20 fullerenes. The activation energies of these processes exceed 2
eV.


title:
PWO Crystal Measurements and Simulation Studies of Lambdabar Hyperon
  Polarisation for PANDA

abstract:
  Two measurements of the energy resolution were performed at MAX-Lab in Lund,
Sweden, with an array of 3$\times$3 PbWO4 crystals using a tagged photon beam
with energies between 19 and 56 MeV. The crystals were cooled down to -15 and
-25 degrees C. The measured relative energy resolution, sigma/E, is decreasing
from approximately 12% at 20 MeV to 7% at 55 MeV. The value of a was therefore
fixed to that one would expect from Poisson statistics of the light collection
yield (50 phe/MeV) and the results from fits were sigma/E= 0.45%/sqrt(E) +
0.18%/E + 8.63% and sigma/E= 0.45%/sqrt(E) + 0.21%/E + 6.12% for the April and
September measurements, respectively. Light yield uniformity studies of five
PbWO4 crystals, three tapered and two non-tapered ones, have also been
performed. The tapered crystals delivered a light output which increased with
increasing distance from the Photo Multiplier Tube (PM tube). For the pbar p ->
Lambdabar Lambda simulations, events were generated using a modified generator
from the PS185 experiment at LEAR. With a 100% polarisation perpendicular to
the scattering plane, a polarisation of (99+-1.8)% was reconstructed. Slight
non-zero polarisations along the axis determined by the outgoing hyperon as
well as the axis in the scattering plane, were also reconstructed. These were
(4.1+-2.1)% and (2.6+-2.0)% respectively. From this investigation it was shown
that the detector efficiency was not homogeneous and that slow pions are
difficult to reconstruct.


title:
Generalized zeta functions, shape invariance and one-loop corrections to
  quantum Kink masses

abstract:
  We present a method to calculate the One-loop mass correction to Kinks mass
in a (1+1)-dimensional field theoretical model in which the fluctuation
potential $V^{\prime\prime}(\phi_c)$ has shape invariance property. We use the
generalized zeta function regularization method to implement our setup for
describing quantum kink states.


title:
Experimental studies of the transient fluctuation theorem using liquid
  crystals

abstract:
  In a thermodynamical process, the dissipation or production of entropy can
only be positive or zero according to the second law of thermodynamics. However
the laws of thermodynamics are applicable to large systems in the thermodynamic
limit. Recently a fluctuation theorem known as the Transient Fluctuation
Theorem (TFT) which generalizes the second law of thermodynamics even for small
systems has been proposed. This theorem has been tested in small systems such
as a colloidal particle in an optical trap. We report for the first time an
analogous experimental study of TFT in a spatially extended system using liquid
crystals.


title:
Fusion cross sections for 6,7Li + 24Mg reactions at energies below and
  above the barrier

abstract:
  Measurement of fusion cross sections for the 6,7Li + 24Mg reactions by the
characteristic gamma-ray method has been done at energies from below to well
above the respective Coulomb barriers. The fusion cross sections obtained from
these gamma-ray cross sections for the two systems are found to agree well with
the total reaction cross sections at low energies. The decrease of fusion cross
sections with increase of energy is consistent with the fact that other
channels, in particular breakup open up with increase of bombarding energy.
This shows that there is neither inhibition nor enhancement of fusion cross
sections for these systems at above or below the barrier. The critical angular
momenta (lcr) deduced from the fusion cross sections are found to have an
energy dependence similar to other Li - induced reactions.


title: Nonlinear Optimization over a Weighted Independence System

abstract:
  We consider the problem of optimizing a nonlinear objective function over a
weighted independence system presented by a linear-optimization oracle. We
provide a polynomial-time algorithm that determines an r-best solution for
nonlinear functions of the total weight of an independent set, where r is a
constant that depends on certain Frobenius numbers of the individual weights
and is independent of the size of the ground set. In contrast, we show that
finding an optimal (0-best) solution requires exponential time even in a very
special case of the problem.


title: Discrete Laplacian Growth: Linear Stability vs Fractal Formation

abstract:
  We introduce stochastic Discrete Laplacian Growth and consider its
deterministic continuous version. These are reminiscent respectively to
well-known Diffusion Limited Aggregation and Hele-Shaw free boundary problem
for the interface propagation. We study correlation between stability of
deterministic free-boundary problem and macroscopic fractal growth in the
corresponding discrete problem. It turns out that fractal growth in the
discrete problem is not influenced by stability of its deterministic version.
Using this fact one can easily provide a qualitative analytic description of
the Discrete Laplacian Growth.

categories: cond-mat.stat-mech math-ph math.MP nlin.PS


title: The thermal phase transition in a QCD-like holographic model

abstract:
  We investigate the high temperature phase of a dilaton flow deformation of
the AdS/CFT Correspondence. We argue that these geometries should be
interpreted as the N=4 gauge theory perturbed by a SO(6) invariant scalar mass
and that the high-temperature phase is just the well-known AdS-Schwarzschild
solution. We compute, within supergravity, the resulting Hawking-Page phase
transition which in this model can be interpreted as a deconfining transition
in which the vev for the operator Tr F^2 dissolves. In the presence of quarks
the model also displays a simultaneous chiral symmetry restoring transition
with the Goldstone mode and other quark bound states dissolving into the
thermal bath.


title: K-edge XANES of substitutional and interstitial Mn atoms in (Ga,Mn)As

abstract:
  This work reports theoretical and experimental study of the X-ray absorption
near-edge structure (XANES) at the Mn K-edge in (Ga,Mn)As diluted magnetic
semiconductors. The spectra have been calculated from the first-principles
using FLAPW including the core-hole effect, a special attention has been paid
to consequences of coexistence of Mn impurities in substitutional and
tetrahedral interstitial positions. We have performed quantitative component
analysis of experimental spectra collected on the (Ga,Mn)As samples
before/after annealing and etching, with the aim to determine the proportion of
Mn impurity configurations. Comparison of the experimental data with
theoretical computations indicates that even after annealing and etching some
Mn atoms still reside in interstitial sites, although the concentration of
interstitial defects has been reduced by annealing.


title:
High precision density measurements in the solar corona: I. Analysis
  methods and results for Fe XII and Fe XIII

abstract:
  The EUV Imaging Spectrometer (EIS) instrument on board the Hinode satellite
has access to some of the best coronal density diagnostics and the high
sensitivity of the instrument now allows electron number density, N_e,
measurements to an unprecedented precision of up to +/-5 % in active regions.
This paper gives a thorough overview of data analysis issues for the best
diagnostics of Fe XII and Fe XIII and assesses the accuracy of the
measurements. Two density diagnostics each from Fe XII (186.88/195.12 and
196.64/195.12) and Fe XIII (196.54/202.04 and 203.82/202.04) are analysed in
two active region data-sets from 2007 May 3 and 6 that yield densities in the
range 8.5 < log N_e < 11.0. The densities are derived using v5.2 of the CHIANTI
atomic database. The Fe XII and Fe XIII diagnostics show broadly the same trend
in density across the active region, consistent with their similar temperatures
of formation. However the high precision of the EIS measurements demonstrates
significant discrepancies of up to 0.5 dex in derived log N_e values, with Fe
XII always giving higher densities than Fe XIII. The discrepancies may partly
be due to real physical differences between the emitting regions of the two
plasmas, but the dominant factor lies in the atomic models of the two ions. Two
specific problems are identified for Fe XII 196.64 and Fe XIII 203.82: the
former is found to be under-estimated in strength by the CHIANTI atomic model,
while the high density limit of the 203.82/202.04 is suggested to be inaccurate
in the CHIANTI atomic model. The small grating tilt of the EIS instrument is
found to be very significant when deriving densities from emission lines
separated by more than a few angstroms.


title: A uniformly spread measure criterion

abstract:
  We prove that if all shifts of a measure in the Euclidean space are close in
a sense to each other, then this measure is close to the Lebesgue one.


title: von Neumann Lattices in Finite Dimensions Hilbert Spaces

abstract:
  The prime number decomposition of a finite dimensional Hilbert space reflects
itself in the representations that the space accommodates. The representations
appear in conjugate pairs for factorization to two relative prime factors which
can be viewed as two distinct degrees freedom. These, Schwinger's quantum
degrees of freedom, are uniquely related to a von Neumann lattices in the phase
space that characterizes the Hilbert space and specifies the simultaneous
definitions of both (modular) positions and (modular) momenta. The area in
phase space for each quantum state in each of these quantum degrees of freedom,
is shown to be exactly $h$, Planck's constant.


title:
The Kormendy Relation for early-type galaxies. Dependence on the
  magnitude range

abstract:
  Previous studies indicate that faint and bright early-type galaxies (ETGs)
present different coefficients and dispersion for their Kormendy relation (KR).
A recently published paper states that the intrinsic dispersion of the KR
depends on the magnitude range within which the galaxies are contained,
therefore, we investigate here whether the magnitude range has also an
influence over the values of the coefficients of the KR; $\alpha$ (zero point)
and $\beta$ (slope). We perform numerical simulations and analysis of these
coefficients for 4 samples of galaxies, which contain an approximate total of
9400 ETGs in a relatively ample magnitude range ($<\Delta M>$ $\sim 6 mag$).
  The analysis of the results makes us conclude that the values of the KR
coefficients depend on the width of the magnitude range and the brightness of
galaxies within the magnitude range. This dependence is due to the fact that
the distribution of galaxies in the $\log (r_{e}) - <\mu>_{e}$ plane depends on
luminosity and that this distribution is not symmetrical, that is, the
geometric shape of the distribution of galaxies in the $\log (r_{e}) -
<\mu>_{e}$ plane plays an important role in the determination of the values of
the coefficients of the KR.


title: Decoherence by Quantum Telegraph Noise

abstract:
  We investigate the time-evolution of a charge qubit subject to quantum
telegraph noise produced by a single electronic defect level. We obtain results
for the time-evolution of the coherence that are strikingly different from the
usual case of a harmonic oscillator bath (Gaussian noise). When the coupling
strength crosses a certain temperature-dependent threshold, we observe
coherence oscillations in the strong-coupling regime. Moreover, we present the
time-evolution of the echo signal in a spin-echo experiment. Our analysis
relies on a numerical evaluation of the exact solution for the density matrix
of the qubit.


title: Correlated Anarchy in Overlapping Wireless Networks

abstract:
  We investigate the behavior of a large number of selfish users that are able
to switch dynamically between multiple wireless access-points (possibly
belonging to different standards) by introducing an iterated non-cooperative
game. Users start out completely uneducated and naive but, by using a fixed set
of strategies to process a broadcasted training signal, they quickly evolve and
converge to an evolutionarily stable equilibrium. Then, in order to measure
efficiency in this steady state, we adapt the notion of the price of anarchy to
our setting and we obtain an explicit analytic estimate for it by using methods
from statistical physics (namely the theory of replicas). Surprisingly, we find
that the price of anarchy does not depend on the specifics of the wireless
nodes (e.g. spectral efficiency) but only on the number of strategies per user
and a particular combination of the number of nodes, the number of users and
the size of the training signal. Finally, we map this game to the well-studied
minority game, generalizing its analysis to an arbitrary number of choices.


title:
The Thermal Production of Strange and Non-Strange Hadrons in e+e-
  Collisions

abstract:
  The thermal multihadron production observed in different high energy
collisions poses two basic problems: (1) why do even elementary collisions with
comparatively few secondaries (e+e- annihilation) show thermal behaviour, and
2) why is there in such interactions a suppression of strange particle
production? We show that the recently proposed mechanism of thermal hadron
production through Hawking-Unruh radiation can naturally account for both. The
event horizon of colour confinement leads to thermal behaviour, but the
resulting temperature depends on the strange quark content of the produced
hadrons, causing a deviation from full equilibrium and hence a suppression of
strange particle production. We apply the resulting formalism to multihadron
production in e+e- annihilation over a wide energy range and make a
comprehensive analysis of the data in the conventional statistical
hadronization model and the modified Hawking-Unruh formulation. We show that
this formulation provides a very good description of the measured hadronic
abundances, fully determined in terms of the string tension and the bare
strange quark mass; it contains no adjustable parameters.


title: On fake lens spaces with the fundamental group of order a power of 2

abstract:
  We present a classification of fake lens spaces of dimension greater or equal
to 5 which have as fundamental group the cyclic group of order N = 2^K, in that
we extend the results of Wall and others in the case N=2.


title: Can a wormhole generate electromagnetic field?

abstract:
  We have considered the possibility of a slowly rotating wormhole surrounded
by a cloud of charged particles. Due to slow rotation of the wormhole, the
charged particles are dragged thereby producing an electromagnetic field. We
have determined the strength of this electromagnetic field and the
corresponding flux of radiation.