Silicon photovoltaic applications

Single-Crystal Silicon. Silicon is still the dominant material in photovoltaic. It has good efficiency, which is 25% in theory and 15% in actual practice. Silicon photovoltaic devices are made from wafers sliced from single crystal silicon ingots, produced in part by CVD (see Ch. 8, Sec. 5.1). However, silicon wafers are still costly, their size is limited, and they cannot be sliced to thicknesses less than 150 im. One crystalline silicon wafer yields only one solar cell, which has an output of only one watt. This means that such cells will always be expensive and can only be used where their high efficiency is essential and cost is not a major factor such as in a spacecraft applications. 

Seager, C.H., and Ginley, D.S., (1982). Fundamental Studies of Grain Boundary Passivation in Polycrystalline Silicon with Application to Improved Photovoltaic Devices, Sandia Report, SAND82-1701, p. 19-21. 

Silicon A semiconductor material made from silica, purified for photovoltaic applications. 

A Method of Defect Characterization in Silicon for Photovoltaic Applications By S. Rein... 

The silicon employed for microelectronic and photovoltaic applications must first go through extensive processing to ensure that the material is of utmost purity. This section will describe these steps, with a discussion of perhaps the most intriguing conversion in the realm of materials science the synthesis of high-purity polished silicon wafers from a naturally occurring form of silicon - sand. 

Nanostructured silicon built-in an anodic alumina is evident to be a promising material for photovoltaic applications. In view of cheap materials and low cost equipment the investigated films could be used for solar cell fabrication on large area substrates. Thus the fabrication of new nanostructures based on silicon clusters built-in an anodic alumina opens new possibilities for nanotechnology in electronics and photonics. 

Czochralski Silicon Crystal Growth for Photovoltaic Applications... 

In all cases, the amount of silicon available for the growth is limited by the solubility at the saturation temperature. For photovoltaic applications, there are also some specific requisites ... 

For silicon, the process can be used to grow films with thicknesses of 1 jtimto >100 nm. Some processes require high substrate temperature, whereas others do not require significant heating of the substrate. For photovoltaic applications, epitaxial silicon is usually grown using liquid-phase epitaxy (LPE) [1-3] and vapor-phase epitaxy (VPE) [4-6], which is a modification of chemical vapor deposition (CVD). 

Discovery of amorphous silicon and its dopability has already had a tremendous impact on industrial applications of amorphous materials. Amorphous Si is now used fairly extensively as a photovoltaic material. In photovoltaic applications, solar photons excite the electrons across the gap and the resulting electron-hole pairs, are driven towards the respective electrodes in order to prevent their recombination. Electron is driven through an external resistance to generate the electrical power. The efficiency of conversion of solar energy to electrical power is characterized by an efficiency factor, r, which is given by. 

Photomultiplier tubes and CCD detectors are the dominant detectors for Raman spectroscopy. Less common detectors include avalanche photodiodes for specialized applications in the near-infrared, single element photovoltaic detectors such as germanium or InGaAs detectors for FT-Raman measurements, and single element silicon photovoltaic detectors for stimulated Raman measurements. 

Nahor A, Berger O, Bardavid Y, Toker G, Tamar Y, Reiss L, Asscher M, Yitzchaik S, Sa ar A (2011) Hybrid structures of porous silicon and conjugated polymers for photovoltaic applications. Physica Stat Solidi (C) Curr Top Solid State Phys 8 1908 Nguyen T-P, Rendu PL, Cheah KW (2003a) Optical properties of porous silicon/poly(p phenylene vinylene) devices. Physica E 17 664... 

Svrcek V, Fujiwara H, Kondo M (2009) Top-down prepared silicon nanocrystals and a conjugated polymer-based bulk heterojunction Optoelectronic and photovoltaic applications. Acta Mater 57 5986... 

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