In our opinion, the frequency shifts of SiC-peak upward indicate a decrease in crystallite size of SiC. We have previously identified size effects, which manifested in the influence of the crystallite sizes of silicon carbide on its optical properties. It was shown (Fig.23) that the differences of the SiC0.03, SiC0.12 and SiC0.4 layers with low carbon concentration from the SiC1.4, SiC0.95 and SiC0.7 layers with high carbon concentration are manifested in the absence +"zw,\$+\*+\*z,!'z+"z %z%\*z 0\$!z z 0.\*/)%//%+\*z /,!0.z \* z%\*z z /\$%"0z 0z DCCC[z+"z)%\*%¥ mum SiC-peak for TO-phonons in the region of wave numbers higher than 800 cm-1\_z\$.¥ teristic for the tetrahedral bonds of crystalline SiC, which is caused by small sizes of SiC .5/0((%0!/zcV 3 nm) and by an increase of contribution in the IR absorption of their surfaces,

Ion Synthesis of SiC and Its Instability at High Temperatures

http://dx.doi.org/10.5772/ 51389

83

Figure 23. 39N=FME:=JG>L@=%.LJ9FKEAKAGFH=9C>GJ0+9F<(+H@GFGFK/A9K9>MF;LAGFG>L@=9FF=9DAF?L=Es

In this case (Fig. 22), the increase of annealing duration of SiC0,7 layer leads to both the shift of the minimum of the IR transmission peak up to 820 cm-1\_z\* z0\$!z.! 10%+\*z+"z0\$!z),(%¥ tude of the LO-phonon peaks and their subsequent disappearance, although SiC0.7z%/z+\*/% ¥ ered as the layer with a high concentration of carbon. At the same time more intense process of the shift of the minimum of SiC-peak occurs after annealing for longer than 8.5 hours, 3\$%\$z(! /z0+z0\$!z %/,,!.\*!z+"z0\$!z,!'z+"zw,\$+\*+\*/^z\$%/z\*z+1.z3\$!\*z0\$!z,!\*!¥ tration of oxygen deep into the layers, their interaction with the carbon atoms on the surface of the crystallites of silicon carbide with the formation of molecules of CO/CO2. Desorption of carbon atoms causes a decrease in the size of the SiC crystallites and their disintegration. With increasing duration of annealing, the homogeneous SiC0.7 layer entirely transforms into

perature: 1 - SiC1.4, 2 - SiC0.95, 3 - SiC0.7, 4 - SiC0.4, 5 - SiC0.12, 6 - SiC0.03.

\* z0\$!z/1."!/z+"z%z.5/0((%0!/z+\*0%\*%\*#z/0.+\*#z/\$+.0z%Pw+\* /z/z3!((^

The value of the wave number of the minimum of SiC-peak of the infrared transmission (the position of the minimum of peak) defines a prevailing kind of optically active bonds which absorb at this wavenumber at this temperature. For the considered layers after annealing at DECC[z"+.zC^Hz\$\_z0\$!z0.\*/)%//%+\*z,!'/z3%0\$z2(1!/z+"z)%\*%)1)z0z32!\*1)!./zKCFz\* KCIz)-1, characteristic of crystalline silicon carbide, are observed (Fig. 22). It was found that with increasing annealing time, the position of the peak minimum varies smoothly and moved in the direction of the wave number increase (Fig. 17 and 22).

Figure 22. Wave number of the minimum of SiC-peak of IR transmission versus the annealing time at 1200°p for the SiC0.7 layers on silicon substrates of (100) and (111) orientations: 1 - Si (111), TO-phonons, 2 - Si(100), TO-phonons, 3 - Si(111), LO-phonons, 4 - Si(100), the LO-phonons.

In our opinion, the frequency shifts of SiC-peak upward indicate a decrease in crystallite size of SiC. We have previously identified size effects, which manifested in the influence of the crystallite sizes of silicon carbide on its optical properties. It was shown (Fig.23) that the differences of the SiC0.03, SiC0.12 and SiC0.4 layers with low carbon concentration from the SiC1.4, SiC0.95 and SiC0.7 layers with high carbon concentration are manifested in the absence +"zw,\$+\*+\*z,!'z+"z %z%\*z 0\$!z z 0.\*/)%//%+\*z /,!0.z \* z%\*z z /\$%"0z 0z DCCC[z+"z)%\*%¥ mum SiC-peak for TO-phonons in the region of wave numbers higher than 800 cm-1\_z\$.¥ teristic for the tetrahedral bonds of crystalline SiC, which is caused by small sizes of SiC .5/0((%0!/zcV 3 nm) and by an increase of contribution in the IR absorption of their surfaces, \* z0\$!z/1."!/z+"z%z.5/0((%0!/z+\*0%\*%\*#z/0.+\*#z/\$+.0z%Pw+\* /z/z3!((^

clusters prevent the crystallization of SiC, and they are less susceptible to oxidation and prevent 0\$!z,!\*!0.0%+\*z+"z+45#!\*z%\*0+z0\$!z%w(5!.^z\$!z%z"%()z+\*zcDCCdz/1/0.0!z\$/z)+.!z-1\*0%¥ ty of stable clusters after implantation and, as a result the smaller value of area of SiC-peak \* z/)((!.z)+1\*0z+"z+,0%((5z0%2!z%Pw+\* /z"0!.z\*\*!(%\*#z"+.zC^Hz\$+1./z\* \_z%0z(!// /1/!,0%(!z0+z+4% 0%+\*z0zDECC[zxzDH^Hz\$zc%\*/0! z+"zDF^Hz\$z"+.zcDDDdz%z/1/0.0!d^z\$!z.!(0%2!(5 rapid decay of close to tetrahedral Si-C bonds (Fig. 20b, curves 2 and 4) led to the decrease 3%0\$z\$%#\$!.z/,!! z+"z0\$!z\*1)!.z+"z+,0%((5z0%2!z%Pw+\* /z%\*z0\$!z/!z+"zcDDDdz+.%!\*0¥ 0%+\*z+"z%z/1/0.0!^z \*z#!\*!.(z 0\$!z !,!\* !\*!z+"z 0\$!z.! 10%+\*z+"z+,0%((5z0%2!z%Pw bonds on the annealing time is linear. This implies that the rapid decay of close to tetrahedral %Pw+\* /z3/z+1..%\*#\_z)%\*(5\_z 1!z0+z0\$!%.z0.\*/"+.)0%+\*z%\*0+zz0!0.\$! .(z+\* ^z\$! linear dependence indicates the homogeneity of the layer, and a rectangular profile of the %/0.%10%+\*z+"z.+\*z0+)/z%\*z/%(%+\*\_z/z3!((z/z0\$!z"0z0\$0z0\$!z !5z.0!z+"z/%(%+\*z.¥ bide does not depend on the depth of the oxidation front. Some decrease in the slope of angle of the curves at the end of the annealing is occurring due to oxidation of the interface "the SiC

The value of the wave number of the minimum of SiC-peak of the infrared transmission (the position of the minimum of peak) defines a prevailing kind of optically active bonds which absorb at this wavenumber at this temperature. For the considered layers after annealing at DECC[z"+.zC^Hz\$\_z0\$!z0.\*/)%//%+\*z,!'/z3%0\$z2(1!/z+"z)%\*%)1)z0z32!\*1)!./zKCFz\* KCIz)-1, characteristic of crystalline silicon carbide, are observed (Fig. 22). It was found that with increasing annealing time, the position of the peak minimum varies smoothly and moved

Figure 22. Wave number of the minimum of SiC-peak of IR transmission versus the annealing time at 1200°p for the SiC0.7 layers on silicon substrates of (100) and (111) orientations: 1 - Si (111), TO-phonons, 2 - Si(100), TO-phonons, 3 -

in the direction of the wave number increase (Fig. 17 and 22).

Si(111), LO-phonons, 4 - Si(100), the LO-phonons.

film – Si substrate".

82 Physics and Technology of Silicon Carbide Devices

Figure 23. 39N=FME:=JG>L@=%.LJ9FKEAKAGFH=9C>GJ0+9F<(+H@GFGFK/A9K9>MF;LAGFG>L@=9FF=9DAF?L=Es perature: 1 - SiC1.4, 2 - SiC0.95, 3 - SiC0.7, 4 - SiC0.4, 5 - SiC0.12, 6 - SiC0.03.

In this case (Fig. 22), the increase of annealing duration of SiC0,7 layer leads to both the shift of the minimum of the IR transmission peak up to 820 cm-1\_z\* z0\$!z.! 10%+\*z+"z0\$!z),(%¥ tude of the LO-phonon peaks and their subsequent disappearance, although SiC0.7z%/z+\*/% ¥ ered as the layer with a high concentration of carbon. At the same time more intense process of the shift of the minimum of SiC-peak occurs after annealing for longer than 8.5 hours, 3\$%\$z(! /z0+z0\$!z %/,,!.\*!z+"z0\$!z,!'z+"zw,\$+\*+\*/^z\$%/z\*z+1.z3\$!\*z0\$!z,!\*!¥ tration of oxygen deep into the layers, their interaction with the carbon atoms on the surface of the crystallites of silicon carbide with the formation of molecules of CO/CO2. Desorption of carbon atoms causes a decrease in the size of the SiC crystallites and their disintegration. With increasing duration of annealing, the homogeneous SiC0.7 layer entirely transforms into SiO2, and then goes the oxidation of the interface "SiC film – Si substrate", in which the car bon concentration decreases uniformly with depth according to a Gaussian law. Thus, the concentration of carbon in the remaining layer begins to decrease. This leads to the appearance of phenomenon which is characteristic for the SiCo12 SiCo03 layers, namely, to shift of the minimum of the IR transmission peak up to 820 cm+, and to a decrease of the amplitude of the LO-phonon peak and their subsequent disappearance. Thus, size effects are confirmed, published by us in 2011.

### 3.3. Parameters of SiC and C films on Si substrates synthesized by magnetron and ionbeam sputtering

#### 3.3.1. Parameters of C films on Si substrates synthesized by by magnetron sputtering

Carbon thin films were obtained by reactive magnetron sputtering using an ARC 2000 system. A graphite target with a diameter ~50 mm and a thickness of 3 mm was used. The magnetron sputtering mode parameters were: cathode voltage U = 470 V, the ion beam current Ion = 35 mA and the argon pressure inside the chamber ~1 Pa. The carbon films were deposited on a set of cleaned silicon substrates. The temperature of the substrate was 75°C.

The presence of a sharp interface "C film - Si substrate" permits to investigate the thickness and density of the film by X-ray reflectometry (CompleXRay C6) by recording the angular dependence of the reflection coefficient using two spectral lines CuK。 (0.154 nm) and CuKo (0.139 nm). The oscillations of intensity were observed, assigned to the interference of X-ray reflections from the boundaries of carbon layer (Fig. 24).

It is known that the density of graphite is 2.2 g/cm³ and the density of diamond - 3.51 g/cm³. Since the density of the resulting film was 3.32 g/cm³ (Table 5 and Fig.24), we concluded that the diamond-like carbon film was synthesized.

Table 5. Determination of the density of the carbon layer by X-ray reflectometry and using the Henke program.

To determine the thickness, five narrow peaks of C, and a broad band of C were used (Fig. 24, table 5).

Table 6. Determination of the thickness of the layers in the system (C - C - Si) by X-ray reflectometry.

Simulation using the Henke program (http://henke.lbl.gov/optical\_constants/) [24] allows to obtain a theoretical curve, which is close to the experimental (Fig.25). The main parameters of the layer system, which allow to obtain an acceptable agreement of experimental and theoretical curves, were:

Thus, diamond-like carbon film of thickness d = 84 nm, density o = 3.3 g/cm³, and surface roughness of o = 1.5 nm on a silicon surface by magnetron sputtering was synthesized.

Figure 24. X-ray reflectometry using two spectral lines CuK, (0.139 nm) (CompleXRay C6) of parameters of carbon films synthesized by magnetron sputtering: a) sample B.

Figure 25. Simulation using the Henke program [24] of experimental results obtained by X-ray reflectometry of parameters of carbon films synthesized by magnetron sputtering.

#### 3.3.2. Parameters of SiC films on Si substrates synthesized by by ion-beam sputtering

SiC films were prepared by ion-beam sputtering. For the simultaneous deposition on silicon substrates of C and Si atoms, a two-component target consisting of the overlapping wafers of silicon and graphite was used. Sputtering of the target was carried out in an argon atmosphere. The formation of Ar ion beam was happening in the ring electrode system (a hollow cathode and an anode), and magnets with crossed electrical and magnetic fields. Discharge power was 108 W (2.7 kV, 40 mA), argon pressure in the chamber 5.9×102 Pa, substrate temperature - 20℃. Samples with SiC films were annealed at 1250℃ in an argon atmosphere for 30 min.

The presence of a sharp interface "the SiC film - Si substrate" permits to investigate the thickness and density of the film by X-ray reflectometry ("ComplexXRay C6"). The oscillations of intensity were observed, assigned to the interference of X-ray reflections from the boundaries of silicon carbide layer (Fig. 26). It is known that the density of graphite is 2.2 g/cm³, and of silicon - 2.33 g/cm³, of silicon carbide - 3.2 g/cm³ and of diamond - 3.51 g/cm³. Since the density of the obtained film was 3.03 g/cm³ (Table 6 and Fig.26), we concluded, that the film close to silicon carbide, was synthesized. The film contains approximately [(3.03-2.33)/ (3.2-2.33)] × 100% = 80.5% SiC, and [(3.2-3.03)/(3.2-2.33)] × 100% = 19.5% Si, i.e., about 80 atoms of C refer per 100 atoms of Si and the SiCgs layer was formed.

Table 7. Determination of the SiC layer by X-ray reflectometry and using the Henke program.

To determine the film thickness the position of maxima of five narrow peaks of SIC was used (Fig.26).

Table 8. Determination of the thickness of the layer in the system (SiC – Si) by X-ray reflectometry.

Simulation using the Henke program (http://henke.lbl.gov/optical\_constants/) [24] allows obtaining a theoretical curve, which is close to the experimental (Fig.27). The main parameters of the layer system, which allow to obtain an acceptable agreement of experimental and theoretical curves, were:

Figure 26. X-ray reflectometry using two spectral lines CuK, (0.139 nm) (CompleXRay C6) parameters of silicon carbide films synthesized by ion-beam sputtering of the two-component target of silicon and graphite.

The film thickness d = 160 nm is different from the values of 180 nm, obtained from the average distance between the peaks 20 ... The reasons for the differences require further studies.

Thus, the silicon carbide film of thickness d = 160 nm, the density o = 3.03 g/cm³, and surface roughness of σ = 0.4 nm on the silicon surface by ion-beam sputtering of the two-component target of silicon and graphite was synthesized.

Figure 27. Simulation using the Henke program [24] of experimental results obtained by X-ray reflectometry of parameters of SiC films synthesized by ion-beam sputtering of the two-component target of silicon and graphite.

#### Conclusion

	- 20-600°C the formation of tetrahedrally oriented Si-C-bonds due to disintegration of clusters which consist mainly of the Si-Si, Si=Si and elongated Si-C-bonds;
	- 600-800°C the formation of Si crystallites and tetrahedrally oriented Si-C-bonds due to disintegration of strained Si-Si bonds and Si-C-bonds, which absorb at frequencies close to 700 and 750 cm², recrystallization starts near the substrate and the surface and goes to the middle of layer;
	- · 800-1000°C begins to dominate the absorption at 800 cm², and near it, due to formation of tetrahedrally oriented bonds of the SiC crystallites, as well as bonds close to tetrahedral;
	- 1000–1100°C the growth of the crystallite size through consolidation of small crystallites of Si and SiC; decay of Si-C-bonds absorbing at 850 and 900 cm³;


*Edited by Stavros Hatzopoulos*

Advances in Clinical Audiology is an excursus on the latest findings in clinical audiology with a strong emphasis in new emerging technologies which facilitate and optimize a better assessment of the human patient. The book has been edited with a strong educational perspective (all chapters include an extensive introduction to their corresponding topic and an extensive glossary of terms). The book contains material suitable for graduate students in audiology, ENT, hearing science, and neuroscience.

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*3.9. Resilience as Surviving or Leaving the Situation*

Some of the participants were exposed to resilient women, giving them permission to expand their visions for themselves and pursue their professional goals and aspirations. One participant shared that her mother is an activist, and she still gets the opportunity to hear her speak about inequities and injustice and continue to do something about it. With admiration she stated, "She's not a person that gives lip service." This participant went on to say that her mother gave her the tools and strategies to deal with the world that in most cases "is not built for people [African American] like me."

Participants highlighted that they had the ability to recognize that they had choices in every situation and had the option to stay or leave.

I remember thinking, well I don't know what to do about that. I'm not leaving my job, so you just get over it. Well, that's a sassier reply than I would have had then, [even though that is what I did].

But there is always that choice you have to make when you are confronted with certain situations where whatever you try will not work with a person, and it is enabling them to continue to be abusive in some way or disrespectful in some way, and then you make a different choice.

I just really felt like if I cannot be in my own truth in this role and in this organization, then this is not the place for me. And I think being solid in that belief is what helped me recover from that.

When I took the job, I had a boss that could not have been better for me. He was hands off. He gave me a project and let me go. I knew instinctively that once his successor took over, it was not going to work. His successor was completely the opposite. He was micromanaging. He was misogynistic. He was very much a narcissist and a tyrant. An interesting example was one of the first meetings I had with him, he was prepping me to go into a meeting. Which is great guidance from a CEO. But at one point he looked at me and said now here's what I want you to say. Been managing to talk since I was about two. Haven't really needed anyone to instruct me. And I left. Actually, it was at that instant I made my decision to leave.

## *3.10. Personal Resilience as a Skill Set*

The resilient behaviors that the participants exhibited to attain and retain their successes are skills that can be developed through coaching, mentoring, and training. The study revealed six mindsets and strategies underlying their successes as illustrated in Table 4 below.

**Table 4.** Resilience Skills: Mindsets and Strategies.

#### **4. Summary and Implications**

The goal of this study was to explore the factors that impact the resilience of successful women leaders who experience disrespect in the workplace. Factors that emerged included early developmental influences, circumstances they faced in their youth and young adulthood, and experiences that shaped how they responded as adults to disrespect or a lack of respect from their organization's stakeholders (e.g., board members, leaders, peers, subordinates, and clients). The study showed that there are five factors that help women leaders develop resilience, including experiences, beliefs, values, people, and events shaping their lives. This study revealed the complexity and variation in the experiences, beliefs, values, people, and events shaping the lives of women in senior leadership positions who are resilient when faced with disrespect in the workplace, including in a virtual environment. Despite these complexities, the study helped to formulate a clearer understanding of how disrespect and respect in the workplace are experienced and whether they impact performance. The women leaders in the study indicated that they did not allow disrespect to impede their performance and that respect did serve to improve their performance.

Although the study revealed that one's upbringing, caretakers, and the influence of certain individuals in one's life contribute to preparing women leaders to being resilient, the study implies that women leaders can still learn certain strategies and work to master particular mindsets to help them become more resilient in the face of disrespect in

the workplace. The implication of these findings is that resilience can be learned to a large extent.

In addition, the pandemic has led to the withdrawal of millions of women from the workplace and their reinsertion into the workplace is moving slowly [25]. There is recognition that changes will need to be made in the post-pandemic workplace for women to be more engaged and satisfied with their work [26]. The implications of this study for the post-pandemic workplace includes the recognition of the importance of respect and the need for organizations to ensure a respectful work environment.

#### *4.1. Study Significance and Limitations*

The study adds to the growing body of literature regarding the characteristics and importance of resilience to the success of women leaders in senior leadership positions. The study also reinforced the importance of respect in the workplace and the potentially negative impact of disrespect on job engagement and satisfaction.

The study was limited in that study participants were already senior women leadership who had successfully exercised resilience against disrespect in the workplace. In addition, the study sample was relatively small and being a purposeful sample, the findings may be limited to the selected group of participants. Because the study was conducted during the COVID-19 pandemic and all interviews were conducted virtually, narratives may have been somewhat different than they would have been if elaborated in face-to-face interview situations where the relationship between researcher and participant could be more personal.


**5. Conclusions**

The regenerative capacity of many stem cells declines functionally with age and, this decline triggers in part many age-related symptoms, and the development of certain diseases. Recent evidences have demonstrated that certain tumor suppressors, like *p16INK4a*, also suppresses the proliferation of stem or progenitor cells in the bone marrow, pancreas and brain. Thus, p16INK4a seems to balance equilibrium reducing cancer incidence, which promotes longevity, but also decreasing stem cell self-renewal and proliferation, compromising tissue regeneration and repair, which are likely to reduce longevity. These observations allow us to suggest the provocative but unproved hypothesis that mammalian aging results in part from the beneficial efforts of tumor suppressor proteins to interdict cancer. In this stage, characterization of how stem cells age, such as **the characterization of reliable biomarkers,** deregulated signaling pathways, loss of self-renewal or acquisition of defects in differentiation of stem cells, will contribute to understand the age-associated pathophysiological decline. Likewise, it is also essential to figure out the cellular and molecular components of stem cell niches, how the niche changes during aging, and

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#### **6. Acknowledgement**

This work was supported by the Human Frontiers Science Program Organization, the Spanish Ministries of Science and Innovation (SAF2010-15386) and Health (FIS PI06/0627). We thank Simon Bartlett for editing assistance. The CNIC is supported by the Ministry of Science and Innovation and the Pro-CNIC Foundation.