where does the silicon in solar panels come from
Polycrystalline silicon - wikipedia Polycrystalline silicon Jump to : navigation , search Left side : solar cells made of multi crystalline silicon Right side : polysilicon rod ( top ) and chunks ( bottom ) Polycrystalline silicon , also called polysilicon or poly - Si , is a high purity , polycrystalline form of silicon , used as a raw material by the solar photovoltaic and electronics industry . Polysilicon is produced from metallurgical grade silicon by a chemical purification process , called the Siemens process . This process involves distillation of volatile silicon compounds , and their decomposition into silicon at high temperatures . An emerging , alternative process of refinement uses a fluidized bed reactor . The photovoltaic industry also produces upgraded metallurgical - grade silicon ( UMG - Si ) , using metallurgical instead of chemical purification processes . When produced for the electronics industry , polysilicon contains impurity levels of less than one part per billion ( ppb ) , while polycrystalline solar grade silicon ( SoG - Si ) is generally less pure . A few companies from China , Germany , Japan , Korea and the United States , such as GCL - Poly , Wacker Chemie , OCI , and Hemlock Semiconductor , as well as the Norwegian headquartered REC , accounted for most of the worldwide production of about 230,000 tonnes in 2013 . The polysilicon feedstock -- large rods , usually broken into chunks of specific sizes and packaged in clean rooms before shipment -- is directly cast into multicrystalline ingots or submitted to a recrystallization process to grow single crystal boules . The products are then sliced into thin silicon wafers and used for the production of solar cells , integrated circuits and other semiconductor devices . Polysilicon consists of small crystals , also known as crystallites , giving the material its typical metal flake effect . While polysilicon and multisilicon are often used as synonyms , multicrystalline usually refers to crystals larger than 1 mm . Multicrystalline solar cells are the most common type of solar cells in the fast - growing PV market and consume most of the worldwide produced polysilicon . About 5 tons of polysilicon is required to manufacture 1 megawatt ( MW ) of conventional solar modules . Polysilicon is distinct from monocrystalline silicon and amorphous silicon . Contents ( hide ) 1 Polycrystalline vs monocrystalline silicon 2 Polycrystalline silicon components 2.1 Feedstock for PV industry 3 Deposition methods 4 Upgraded metallurgical - grade silicon 5 Potential for use of polycrystalline silicon 6 Novel ideas for polycrystalline silicon 7 Manufacturers 7.1 Capacity 7.2 Price 7.2. 1 Dumping 7.2. 2 Waste 8 See also 9 References 10 External links Polycrystalline vs. monocrystalline silicon ( edit ) Comparing polycrystalline ( left ) to monocrystalline ( right ) solar cells In single crystal silicon , also known as monocrystalline silicon , the crystalline framework is homogenous , which can be recognized by an even external colouring . The entire sample is one single , continuous and unbroken crystal as its structure contains no grain boundaries . Large single crystals are rare in nature and can also be difficult to produce in the laboratory ( see also recrystallisation ) . In contrast , in an amorphous structure the order in atomic positions is limited to short range . Polycrystalline and paracrystalline phases are composed of a number of smaller crystals or crystallites . Polycrystalline silicon ( or semi-crystalline silicon , polysilicon , poly - Si , or simply `` poly '' ) is a material consisting of multiple small silicon crystals . Polycrystalline cells can be recognized by a visible grain , a `` metal flake effect '' . Semiconductor grade ( also solar grade ) polycrystalline silicon is converted to `` single crystal '' silicon -- meaning that the randomly associated crystallites of silicon in `` polycrystalline silicon '' are converted to a large `` single '' crystal . Single crystal silicon is used to manufacture most Si - based microelectronic devices . Polycrystalline silicon can be as much as 99.9999 % pure . Ultra-pure poly is used in the semiconductor industry , starting from poly rods that are two to three meters in length . In microelectronic industry ( semiconductor industry ) , poly is used both at the macro-scale and micro-scale ( component ) level . Single crystals are grown using the Czochralski process , float - zone and Bridgman techniques . Polycrystalline silicon components ( edit ) This section does not cite any sources . Please help improve this section by adding citations to reliable sources . Unsourced material may be challenged and removed . ( January 2014 ) ( Learn how and when to remove this template message ) A rod of semiconductor - grade polysilicon . At the component level , polysilicon has long been used as the conducting gate material in MOSFET and CMOS processing technologies . For these technologies it is deposited using low - pressure chemical - vapour deposition ( LPCVD ) reactors at high temperatures and is usually heavily doped n - type or p - type . More recently , intrinsic and doped polysilicon is being used in large - area electronics as the active and / or doped layers in thin - film transistors . Although it can be deposited by LPCVD , plasma - enhanced chemical vapour deposition ( PECVD ) , or solid - phase crystallization of amorphous silicon in certain processing regimes , these processes still require relatively high temperatures of at least 300 ° C. These temperatures make deposition of polysilicon possible for glass substrates but not for plastic substrates . The deposition of polycrystalline silicon on plastic substrates is motivated by the desire to be able to manufacture digital displays on flexible screens . Therefore , a relatively new technique called laser crystallization has been devised to crystallize a precursor amorphous silicon ( a-Si ) material on a plastic substrate without melting or damaging the plastic . Short , high - intensity ultraviolet laser pulses are used to heat the deposited a-Si material to above the melting point of silicon , without melting the entire substrate . Polycrystalline silicon ( used to produce silicon monocrystals by Czochralski process ) The molten silicon will then crystallize as it cools . By precisely controlling the temperature gradients , researchers have been able to grow very large grains , of up to hundreds of micrometers in size in the extreme case , although grain sizes of 10 nanometers to 1 micrometer are also common . In order to create devices on polysilicon over large - areas however , a crystal grain size smaller than the device feature size is needed for homogeneity of the devices . Another method to produce poly - Si at low temperatures is metal - induced crystallization where an amorphous - Si thin film can be crystallized at temperatures as low as 150 ° C if annealed while in contact of another metal film such as aluminium , gold , or silver . Polysilicon has many applications in VLSI manufacturing . One of its primary uses is as gate electrode material for MOS devices . A polysilicon gate 's electrical conductivity may be increased by depositing a metal ( such as tungsten ) or a metal silicide ( such as tungsten silicide ) over the gate . Polysilicon may also be employed as a resistor , a conductor , or as an ohmic contact for shallow junctions , with the desired electrical conductivity attained by doping the polysilicon material . One major difference between polysilicon and a-Si is that the mobility of the charge carriers of the polysilicon can be orders of magnitude larger and the material also shows greater stability under electric field and light - induced stress . This allows more complex , high - speed circuity to be created on the glass substrate along with the a-Si devices , which are still needed for their low - leakage characteristics . When polysilicon and a-Si devices are used in the same process this is called hybrid processing . A complete polysilicon active layer process is also used in some cases where a small pixel size is required , such as in projection displays . Feedstock for PV industry ( edit ) Main article : Crystalline silicon Polycrystalline silicon is the key feedstock in the crystalline silicon based photovoltaic industry and used for the production of conventional solar cells . For the first time , in 2006 , over half of the world 's supply of polysilicon was being used by PV manufacturers . The solar industry was severely hindered by a shortage in supply of polysilicon feedstock and was forced to idle about a quarter of its cell and module manufacturing capacity in 2007 . Only twelve factories were known to produce solar - grade polysilicon in 2008 ; however , by 2013 the number increased to over 100 manufacturers . Monocrystalline silicon is higher priced and a more efficient semiconductor than polycrystalline as it went through the additional recrystallization by the Czochralski process . Deposition methods ( edit ) Polysilicon deposition , or the process of depositing a layer of polycrystalline silicon on a semiconductor wafer , is achieved by the chemical decomposition of silane ( SiH ) at high temperatures of 580 to 650 ° C . This pyrolysis process releases hydrogen . SiH 4 ( g ) → Si ( s ) + 2 H 2 ( g ) CVD at 500 - 800 C Polysilicon layers can be deposited using 100 % silane at a pressure of 25 -- 130 Pa ( 0.19 -- 0.98 Torr ) or with 20 -- 30 % silane ( diluted in nitrogen ) at the same total pressure . Both of these processes can deposit polysilicon on 10 -- 200 wafers per run , at a rate of 10 -- 20 nm / min and with thickness uniformities of ± 5 % . Critical process variables for polysilicon deposition include temperature , pressure , silane concentration , and dopant concentration . Wafer spacing and load size have been shown to have only minor effects on the deposition process . The rate of polysilicon deposition increases rapidly with temperature , since it follows Arrhenius behavior , that is deposition rate = A exp ( -- qE / kT ) where q is electron charge and k is the Boltzmann constant . The activation energy ( E ) for polysilicon deposition is about 1.7 eV . Based on this equation , the rate of polysilicon deposition increases as the deposition temperature increases . There will be a minimum temperature , however , wherein the rate of deposition becomes faster than the rate at which unreacted silane arrives at the surface . Beyond this temperature , the deposition rate can no longer increase with temperature , since it is now being hampered by lack of silane from which the polysilicon will be generated . Such a reaction is then said to be ' mass - transport - limited . ' When a polysilicon deposition process becomes mass - transport - limited , the reaction rate becomes dependent primarily on reactant concentration , reactor geometry , and gas flow . When the rate at which polysilicon deposition occurs is slower than the rate at which unreacted silane arrives , then it is said to be surface - reaction - limited . A deposition process that is surface - reaction - limited is primarily dependent on reactant concentration and reaction temperature . Deposition processes must be surface - reaction - limited because they result in excellent thickness uniformity and step coverage . A plot of the logarithm of the deposition rate against the reciprocal of the absolute temperature in the surface - reaction - limited region results in a straight line whose slope is equal to -- qE / k . At reduced pressure levels for VLSI manufacturing , polysilicon deposition rate below 575 ° C is too slow to be practical . Above 650 ° C , poor deposition uniformity and excessive roughness will be encountered due to unwanted gas - phase reactions and silane depletion . Pressure can be varied inside a low - pressure reactor either by changing the pumping speed or changing the inlet gas flow into the reactor . If the inlet gas is composed of both silane and nitrogen , the inlet gas flow , and hence the reactor pressure , may be varied either by changing the nitrogen flow at constant silane flow , or changing both the nitrogen and silane flow to change the total gas flow while keeping the gas ratio constant . Recent investigations have shown that e-beam evaporation , followed by SPC ( if needed ) can be a cost effective and faster alternative for producing solar grade poly - Si thin films . Modules produced by such method are shown to have a photovoltaic efficiency of ~ 6 % . Polysilicon doping , if needed , is also done during the deposition process , usually by adding phosphine , arsine , or diborane . Adding phosphine or arsine results in slower deposition , while adding diborane increases the deposition rate . The deposition thickness uniformity usually degrades when dopants are added during deposition . Upgraded metallurgical - grade silicon ( edit ) Schematic diagram of the traditional Siemens and the Fluidized bed reactor purification process . Upgraded metallurgical - grade ( UMG ) silicon ( also known as UMG - Si ) solar cell is being produced as a low cost alternative to polysilicon created by the Siemens process . UMG - Si greatly reduces impurities in a variety of ways that require less equipment and energy than the Siemens process . It is about 99 % pure which is three or more orders of magnitude less pure and about 10 times less expensive than polysilicon ( $1.70 to $3.20 per kg from 2005 to 2008 compared to $40 to $400 per kg for polysilicon ) . It has the potential to provide nearly - as - good solar cell efficiency at 1 / 5 the capital expenditure , half the energy requirements , and less than $15 / kg . In 2008 several companies were touting the potential of UMG - Si in 2010 , but the credit crisis greatly lowered the cost of polysilicon and several UMG - Si producers put plans on hold . The Siemens process will remain the dominant form of production for years to come due to more efficiently implementing the Siemens process . GT Solar claims a new Siemens process can produce at $27 / kg and may reach $20 / kg in 5 years . GCL - Poly expects production costs to be $20 / kg by end of 2011 . Elkem Solar estimates their UMG costs to be $25 / kg , with a capacity of 6,000 tonnes by the end of 2010 . Calisolar expects UMG technology to produce at $12 / kg in 5 years with boron at 0.3 ppm and phosphorus at 0.6 ppm . At $50 / kg and 7.5 g / W , module manufacturers spend $0.37 / W for the polysilicon . For comparison , if a CdTe manufacturer pays spot price for tellurium ( $420 / kg in April 2010 ) and has a 3 μm thickness , their cost would be 10 times less , $0.037 / Watt . At 0.1 g / W and $31 / ozt for silver , polysilicon solar producers spend $0.10 / W on silver . Q - Cells , Canadian Solar , and Calisolar have used Timminco UMG . Timminco is able to produce UMG - Si with 0.5 ppm boron for $21 / kg but were sued by shareholders because they had expected $10 / kg . RSI and Dow Corning have also been in litigation over UMG - Si technology . Potential for use of polycrystalline silicon ( edit ) A picture of grain boundaries for polysilicon . Each grain is crystalline over the width of the grain . The grain boundary separates the grains where the adjoining grain is at a different orientation from its neighbor . The grain boundary separates regions of different crystal structure thus serving as a center for recombination . ' d ' here is a characteristic grain size , which should be maximized for maximum solar cell efficiency . Typical values of d are about 1 micrometre . Currently , polysilicon is commonly used for the conducting gate materials in semiconductor devices such as MOSFETs ; however , it has potential for large - scale photovoltaic devices . The abundance , stability , and low toxicity of silicon , combined with the low cost of polysilicon relative to single crystals makes this variety of material attractive for photovoltaic production . Grain size has been shown to have an effect on the efficiency of polycrystalline solar cells . Solar cell efficiency increases with grain size . This effect is due to reduced recombination in the solar cell . Recombination , which is a limiting factor for current in a solar cell , occurs more prevalently at grain boundaries , see figure 1 . The resistivity , mobility , and free - carrier concentration in monocrystalline silicon vary with doping concentration of the single crystal silicon . Whereas the doping of polycrystalline silicon does have an effect on the resistivity , mobility , and free - carrier concentration , these properties strongly depend on the polycrystalline grain size , which is a physical parameter that the material scientist can manipulate . Through the methods of crystallization to form polycrystalline silicon , an engineer can control the size of the polycrystalline grains which will vary the physical properties of the material . Novel ideas for polycrystalline silicon ( edit ) The use of polycrystalline silicon in the production of solar cells requires less material and therefore provides higher profits and increased manufacturing throughput . Polycrystalline silicon does not need to be deposited on a silicon wafer to form a solar cell , rather it can be deposited on other - cheaper materials , thus reducing the cost . Not requiring a silicon wafer alleviates the silicon shortages occasionally faced by the microelectronics industry . An example of not using a silicon wafer is crystalline silicon on glass ( CSG ) materials A primary concern in the photovoltaics industry is cell efficiency . However , sufficient cost savings from cell manufacturing can be suitable to offset reduced efficiency in the field , such as the use of larger solar cell arrays compared with more compact / higher efficiency designs . Designs such as CSG are attractive because of a low cost of production even with reduced efficiency . Higher efficiency devices yield modules that occupy less space and are more compact ; however , the 5 -- 10 % efficiency of typical CSG devices still makes them attractive for installation in large central - service stations , such as a power station . The issue of efficiency versus cost is a value decision of whether one requires an `` energy dense '' solar cell or sufficient area is available for the installation of less expensive alternatives . For instance , a solar cell used for power generation in a remote location might require a more highly efficient solar cell than one used for low - power applications , such as solar accent lighting or pocket calculators , or near established power grids . Manufacturers ( edit ) Capacity ( edit ) Polysilicon production by country in 2013 ( company head - quarter , not location of facility ) . World total of 227,000 tonnes . China ( 36.1 % ) USA ( 25.9 % ) South Korea ( 11.4 % ) Germany ( 21.6 % ) Japan ( 4.9 % ) Chemical processing at a P.S.T. polysilicon plant The polysilicon manufacturing market is growing rapidly . According to Digitimes , in July 2011 , the total polysilicon production in 2010 was 209,000 tons . First - tier suppliers account for 64 % of the market while China - based polysilicon firms have 30 % of market share . The total production is likely to increase 37.4 % to 281,000 tons by end of 2011 . For 2012 , EETimes Asia predicts 328,000 tons production with only 196,000 tons of demand , with spot prices expected to fall 56 % . While good for renewable energy prospects , the subsequent drop in price could be brutal for manufacturers . As of late 2012 , SolarIndustryMag reports a capacity of 385,000 tons will be reached by yearend 2012 . But as established producers ( mentioned below ) expand their capacities , additional newcomers -- many from Asia -- are moving into the market . Even long - time players in the field have recently had difficulties expanding plant production . It is yet unclear which companies will be able to produce at costs low enough to be profitable after the steep drop in spot - prices of the last months . Leading producer capacities . Wacker 's projected its total hyperpure - polysilicon production capacity to increase to 67,000 metric tons by 2014 , due to its new polysilicon - production facility in Cleveland , Tennessee ( USA ) with an annual capacity of 15,000 metric tons . <Th_colspan="4"> Largest Polysilicon Producers in 2013 ( market - share in % ) GCL - Poly Energy China 65,000 tons 22 % Wacker Chemie Germany 52,000 tons 17 % OCI South Korea 42,000 tons 14 % Hemlock Semiconductor USA 36,000 tons 12 % REC Norway 21,500 tons 7 % <Th_colspan="4"> Source : Market Realist cites World production capacity at 300,000 tons in 2013 . BNEF estimated actual production for 2013 at 227,000 tons Other manufacturers LDK Solar ( 2010 : 15 kt ) China . Tokuyama Corporation ( 2009 : 8 kt , Jan 2013 : 11 kt , 2015 : 31 kt ) Japan . MEMC / SunEdison ( 2010 : 8 kt , Jan 2013 : 18 kt ) USA . Hankook Silicon ( 2011 : 3.2 kt , 2013 : 14.5 kt ) Nitol Solar , ( 2011 : 5 kt , Jan 2011 ) , Russia Mitsubishi Polysilicon ( 2008 : 4.3 kt ) Osaka Titanium Technologies ( 2008 : 4.2 kt ) Daqo , ( 2011 : 4.3 kt , under construction 3 kt ) , China Beijing Lier High - temperature Materials Co. ( 2012 : 5 kt ) Qatar Solar Technologies , at Ras Laffan , announced an 8,000 mt facility for start in 2013 . Price ( edit ) History of polysilicon spot prices Prices of polysilicon are often divided into two categories , contract and spot prices , and higher purity commands higher prices . While in booming installation times , price rally occurs in polysilicon . Not only spot prices surpass contract prices in the market ; but it is also hard to acquire enough polysilicon . Buyers will accept down payment and long term agreements to acquire a large enough volume of polysilicon . On the contrary , spot prices will be below contract prices once the solar PV installation is in a down trend . In late 2010 , booming installation brought up the spot prices of polysilicon . In the first half of 2011 , prices of polysilicon kept strong owing to the FIT policies of Italy . The solar PV price survey and market research firm , PVinsights , reported that the prices of polysilicon might be dragged down by lack of installation in the second half of 2011 . As recently as 2008 prices were over $400 / kg spiking from levels around $200 / kg , while seen falling to $15 / kg in 2013 . Dumping ( edit ) The Chinese government accused United States and South Korean manufacturers of predatory pricing or `` dumping '' . As a consequence , it imposed import tariffs of as much as 57 percent on polysilicon shipped from these two countries in order to stop the product from being sold below cost . Waste ( edit ) Due to the rapid growth in manufacturing in China and the lack of regulatory controls , there have been reports of the dumping of waste silicon tetrachloride . Normally the waste silicon tetrachloride is recycled but this adds to the cost of manufacture as it needs to be heated to 1,800 ° F ( 980 ° C ) See also ( edit ) Wikimedia Commons has media related to Polycrystalline silicon solar cells . Bulk Metallurgical grade silicon Wafer ( electronics ) Polycrystal Nanocrystalline silicon Amorphous silicon Cadmium telluride Thin - film solar cell Solar cell Photovoltaic module Photovoltaics References ( edit ) ^ Jump up to : `` Solar Insight , Research note -- PV production 2013 : an all Asian - affair '' ( PDF ) . Bloomberg New Energy Finance . 16 April 2014 . pp. 2 -- 3 . Archived from the original on 30 April 2015 . ^ Jump up to : `` China : The new silicon valley -- Polysilicon '' . 2 February 2015 . Archived from the original on 30 April 2015 . Jump up ^ Solar ABC Jump up ^ Kolic , Y ( 1995 ) . `` Electron powder ribbon polycrystalline silicon plates used for porous layer fabrication '' . Thin Solid Films. 255 : 159 . Bibcode : 1995TSF ... 255 ... 159K . doi : 10.1016 / 0040 - 6090 ( 94 ) 05644 - S . Jump up ^ Photovoltaics : Getting Cheaper Jump up ^ The Wall Street Journal , A Shortage Hits Solar Power . April 29 , 2006 . Jump up ^ http://www.enfsolar.com/directory/material/polysilicon Jump up ^ Morgan , D.V. ; Board , K. ( 1991 ) . An Introduction To Semiconductor Microtechnology ( 2nd ed . ) . Chichester , West Sussex , England : John Wiley & Sons . p. 27 . ISBN 0471924784 . access - date = requires url = ( help ) Jump up ^ C. Becker , Microstructure and photovoltaic performance of polycrystalline silicon thin films on temperature - stable ZnO : Al layers . J. Appl . Phys. 106 , 084506 ( 2009 ) , DOI : 10.1063 / 1.3240343 Jump up ^ ( 35th IEEE Photovoltaic Specialists Conference , 614 ( 2010 ) ) Jump up ^ Is Upgraded Metallurgical Grade Silicon The Only Hope For Manufacturers of Photovoltaic Solar Cells ? -- GLG News . Glgroup.com ( 2008 - 05 - 20 ) . Retrieved on 2011 - 04 - 02 . Jump up ^ Dow Corning stopped UMG Solar Grade Silicon Production . GUNTHER Portfolio ( 2010 - 04 - 29 ) . Retrieved on 2011 - 04 - 02 . Jump up ^ Dow Corning stopped UMG Solar Grade Silicon Production . GUNTHER Portfolio ( 2010 - 04 - 29 ) . Retrieved on 2011 - 04 - 02 . Jump up ^ Press Release . Timminco . Retrieved on 2011 - 04 - 02 . Jump up ^ http://www.solarserver.com/solar-magazine/solar-news/current/kw49/oci-aims-to-become-worlds-largest-polysilicon-producer-with-27000mty-expansion.html Jump up ^ http://www.bernreuter.com/fileadmin/user_upload/samples/SWE_6-2010_Solar_Silicon_Conference.pdf Jump up ^ http://www.virtualmetals.co.uk/pdf/FBNSB0610.pdf Jump up ^ The Who 's Who of Solar Silicon Production , Companies , Technologies , Cost , Capacities , Global Perspectives through 2012 Jump up ^ Solar Grade Litigation : Dow Corning vs. RSI Silicon . GUNTHER Portfolio . Retrieved on 2011 - 04 - 02 . Jump up ^ Streetman , B.G. & Banerjee , S. ( 2000 ) , Solid State Electronic Devices ( 5th ed . ) , New Jersey : Prentice Hall , ISBN 0 - 13 - 025538 - 6 . ^ Jump up to : Ghosh , Amal K. ; Fishman , Charles & Feng , Tom ( 1980 ) , `` Theory of the electrical and photovoltaic properties of polycrystalline silicon '' , Journal of Applied Physics , 51 ( 1 ) : 446 , Bibcode : 1980JAP ... 51 ... 446G , doi : 10.1063 / 1.327342 . ^ Jump up to : Basore , P.A. ( 2006 ) , `` CSG - 2 : Expanding the production of a new polycrystalline silicon PV technology '' ( PDF ) , Proceedings of the 21st European Photovoltaic Solar Energy Conference . Jump up ^ http://www.digitimes.com/news/a20110718PD215.html Jump up ^ http://www.eetasia.com/ART_8800665769_765245_NT_5e271e8d.HTM Jump up ^ http://solarindustrymag.com/e107_plugins/content/content.php?content.11295 Jump up ^ Commerzbank Equity Research , Robert Schramm , Lauren Licuanan : Feedback form Solar Silicon Conference . 28 . April 2010 Jump up ^ Citigroup Global Markets , Timothy Lam : Asia Solar View -- May 2010 , 3 . May 2010 Jump up ^ http://www.wacker.com WACKER TENNESSEE Frequently Asked Questions , 2015 Jump up ^ Presseportal Wacker Chemie Kapazität Polysilicon Jump up ^ LDK Solar Jump up ^ http://www.solarserver.com/solar-magazine/solar-news/current/2011/kw19/tokuyama-corporation-to-construct-new-polysilicon-plants-in-japan-and-malaysia.html Jump up ^ http://www.tokuyama.co.jp/eng/company/business/specialtyproducts/electronic.html Jump up ^ http://www.tokuyama.co.jp/eng/ir/report/briefing/pdf/2011mar_2ndQ_setsumeikai_e.pdf Jump up ^ MEMC -- About MEMC Jump up ^ http://www.chemicalonline.com/article.mvc/Samsung-Fine-Chemicals-And-MEMC-Sign-0001 Jump up ^ http://www.solarserver.com/solar-magazine/solar-news/current/2011/kw15/hankook-silicon-achieves-3200-mty-polysilicon-production-at-yesou-korea-plant.html Jump up ^ Nitol polysilicon production comes on line , RT , 2011 - 01 - 05 ^ Jump up to : http://www.greenrhinoenergy.com/solar/industry/ind_01_silicon.php Jump up ^ http://news.businessweek.com/article.asp?documentKey=1376-LNWOBG1A74E901-18V2TMP81AU917V753QK4RH4QD Jump up ^ `` Beijing Lier Plans 1.4 Billion Yuan Polysilicon Project in Henan '' . Bloomberg. 2011 - 07 - 12 . Jump up ^ http://www.gulf-times.com/site/topics/article.asp?cu_no=2&item_no=462158&version=1&template_id=57&parent_id=56 Gulf Times Ras Laffan to get $1 bn polysilicon plant Jump up ^ PVinsights Jump up ^ ( Price cut of solar PV supply chain spreads and the price of poly - silicon might be dragged down by others Jump up ^ http://www.digitimes.com/news/a20121123PD204.html Jump up ^ `` China Imposes Duties on Polysilicon From U.S. , S. Korea '' . Bloomberg. 18 July 2013 . Retrieved 18 July 2013 . Jump up ^ `` Solar Energy Firms Leave Waste Behind in China '' . Washington Post . 9 March 2008 . Retrieved 8 March 2015 . External links ( edit ) Alan Joch ( November 10 , 2006 ) . `` Sand Trap : Will the silicon shortage stunt the solar industry 's growth ? '' . Plenty Magazine . Retrieved from `` https://en.wikipedia.org/w/index.php?title=Polycrystalline_silicon&oldid=813212862 '' Categories : Group IV semiconductors Crystals Silicon solar cells Silicon forms Hidden categories : Pages using citations with accessdate and no URL Articles needing additional references from January 2014 All articles needing additional references Commons category without a link on Wikidata Talk Contents About Wikipedia Eesti Español Français Italiano Polski Português Русский Suomi Türkçe 中文 Edit links This page was last edited on 2 December 2017 , at 13 : 06 . Text is available under the Creative Commons Attribution - ShareAlike License ; additional terms may apply . By using this site , you agree to the Terms of Use and Privacy Policy . Wikipedia ® is a registered trademark of the Wikimedia Foundation , Inc. , a non-profit organization . About Wikipedia
1. Polycrystalline silicon production
2. Applications of polycrystalline silicon
3. Polycrystalline vs monocrystalline silicon
4. Deposition methods for polycrystalline silicon
5. Potential and novel ideas for polycrystalline silicon