Silicon in solar cells

Yerokhov, V. Yu. and Mehiyk I. I. Eorous silicon in solar cell structures , (1999) Renew. Sust. Energ. Rev. 3,291-322. 

Menna P, Di Francia G, La Ferrara V (1995) Porous silicon in solar cells a review and a description of its application as an AR coating. Sol Energy Mater Sol Cells 37 13-24 Najar A, Charrier J, Pilasteh P, Sougrata R (2012) Ultra-low reflection porous silicon nanowires for solar cell applications. Acta Phys Pol A 122 1121-1124 Nelson J (2003) Physics of solar cells. World Scientific, Washington, DC Panek P (2004) Elfect of macroporous silicon layer on opto-electrical parameters of multicrystalline silicon solar cells. Opto Electron Rev 12 45—48... 

Yerokhov VY, Melnyk I (1999) Porous silicon in solar cell structures a review of achievements and modem directions of further use. Renew Sustain Energy Rev 3 291-322... 

Yerokhov V, Melnik I, Tsisaruk A, Semochko I (2000) Porous silicon in solar cell stmctures. Opto Electron Rev 8 414-417... 

SILICON AND SILICON ALLOYS - PURE SILICON] (Vol 21) -in solar cells PHOTOVOLTAIC CELLS] (Vol 18)... 

Limitations of Plasma CVD. With plasma CVD, it is difficult to obtain a deposit of pure material. In most cases, desorption of by-products and other gases is incomplete because of the low temperature and these gases, particularly hydrogen, remain as inclusions in the deposit. Moreover, in the case of compounds, such as nitrides, oxides, carbides, or silicides, stoichiometry is rarely achieved. This is generally detrimental since it alters the physical properties and reduces the resistance to chemical etching and radiation attack. However in some cases, it is advantageous for instance, amorphous silicon used in solar cells has improved optoelectronic properties if hydrogen is present (see Ch. 15). 

Silicon solar-cells are fabricated using silicon discs in a manner similar to that described previously for manufacture of integrated circuits. The basic external structure used in solar cells is shown in the following diagram ... 

The majority of important semiconducting materials are isoelectronic with elemental silicon. Important semiconductor materials include the III-V (13-15) materials such as GaAs or InP, and II-VI (12-16) materials such as CdS or ZnSe (Table 1). These compound semiconductors are most often formed by combining elements displaced on either side of silicon by one place (i.e., Ill = Ga or In and V = N or As for a III-V material) or two places (i.e., II = Zn or Cd and VI = S or Se for a II-VI material) in the periodic table. Other materials are of specialist importance, especially ternary materials such as CuInE2 (E = S and Se), which find applications in solar cell technologies, as do materials of III-VI composition such as InxS, although their properties are often complicated by the potential for the formation of a wide range of similar phases. 

Guha S, Yang J, Nath P, Hack M (1986) Enhancement of open circuit voltage in high-efficiency amorphous-silicon alloy solar-cells. Appl Phys Lett 49 218 Hack M, Shur M (1985) Physics of amorphous-silicon alloy p-i-n solar-cells. J Appl Phys 58 997... 

In many cases, the deposited material can retain some of the original chemical constituents, such as hydrogen in silicon from the deposition from silane, or chlorine in tungsten from the deposition from WC1 . This can be beneficial or detrimental. For example, the retention of hydrogen in silicon allows the deposition of amorphous silicon, a-Si H, which is used in solar cells, but the retention of chlorine in tungsten is detrimental to subsequent fusion welding of the tungsten. 

Four different types of junctions can be used to separate the charge earners in solar cells (1) a homojunction joins semiconductor materials of the same substance, e.g., the homojunction of a p — n silicon solar cell separates two oppositely doped layers of silicon (2) a heterojunction is formed between two dissimilar semiconductor substances, e.g., copper sulfide, Cu S, and cadmium sulfide, CdS, in CuxS—CdS solar cells (3) a Schottky junction is formed when a metal and semiconductor material are joined and (4) in a metal-insulator-semiconductor junction (MIS), a thin insulator layer, generally less than 0.003-pim thick, is sandwiched between a metal and semiconductor material. 

Silicon Nitride. Silicon nitride produced by high-temperature (>700 °C) CVD is a dense, stable, adherent dielectric that is useful as a passivation or protective coating, interlevel metal dielectric layer, and antireflection coating in solar cells and photodetectors. However, these applications often demand low deposition temperatures (<400 °C) so that low-melting-point substrates or films (e.g., Al or polymers) can be coated. Therefore, considerable effort has been expended to form high-quality silicon nitride films by PECVD. 

In the present chapter, we will review the nature of plasma-enhanced CVD (PECVD) films for a variety of applications. We will look at dielectrics (silicon nitride, silicon dioxide), semiconductors (polysilicon, epi silicon) and metals (refractory metals, refractory metal silicides, aluminum). There are many other important films (i.e., amorphous silicon for solar cells and TiN for tool harden-... 

In this article, we first review the methods of growing amorphous silicon for solar cells. The next part covers the material properties that are relevant to the development of efficient, stable a-Si H solar cells. In Part IV, we discuss the fabrication, performance, and scale-up of a-Si H solar cells, and in Part V, we consider the economics of these cells for various applications. We conclude with some projections for the future of a-Si H photovoltaics. 

H. Kobayashi, J. Ono, T. Ishida, M. Okamoto, H. Kawanaka, and H. Tsubomura, Mechanism of photocurrent and photovoltage in solar cells using n-silicon electrodes in non-aqueous solutions, J. Elec-troanal. Chem. 312, 57, 1991. 

Single and polycrystalline silicon is utilized in solar cells for photovoltaic electricity production. 

Chemists are studying the structure and kinetics of the photosynthetic reaction center both to understand the fundamentals of this important natural process and to design new materials that mimic nature s ability to harvest light energy at such high efficiency. Artificial photosynthesis may lead to carbon-based materials that will replace the silicon collectors in solar cells in the 21st century. This will help reduce human dependence on stored fossil fuels as energy sources in the future. 

Multicrystalline silicon (mc-Si) has a large demand of photovoltaics to overcome difficulty of the present green problem [1]. The directional solidification method is a key method for large-scale production of mc-Si in highly efficient solar cells. The maximum efficiency of the solar cell based on mc-Si is 18%. However, the use of commercially available wafers typically results in solar cell efficiency of about 16% in industrial solar cell processes. 

Since the concentrations of impurities in solar cell grade silicon are in the range from ppb to a few percent, it is not necessary to take ternary interaction parameters into account. The activity coefficient of impurity, i , in a n-tli multicomponent system is given by differentiating (13.3) ... 

Effect of Solubility, Distribution Coefficient, and Stable Precipitates in Solar Cell Grade Silicon... 

This book, a continuation of the series Advances in Materials Research, is intended to provide the general basis of the science and technology of crystal growth of silicon for solar cells. In the face of the destruction of the global environment, the degradation of world-wide natural resources and the exhaustion of energy sources in the twenty-first century, we all have a sincere desire for a better/safer world in the future. 

Pure silicon is used in solar cells to collect energy from the sun. 

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