Silicon semiconduction

Crystalline solar cells are heavy and expensive to manufacture. However, their efficiency in converting sunlight has historically been superior to thin-film. Crystalline cells are constructed with silicon semiconducting materials. 

M. G. Bradley and T. Tysak, p-type silicon based photoelectrochemical cells for optical energy conversion Electrochemistry of tetra-azomacrocyclic metal complexes at illuminated p-type silicon semiconducting electrodes, J. Electroanal. Chem. 135, 153, 1982. 

Bradley MG, Tysak T, Graves DJ, Viachiopoulos NA (1983) Electrocatalytic reduction of carbon dioxide at illuminated p-type silicon semiconducting electrodes. J Chem Soc Chem Commun 7 349-350... 

Typical results for a semiconducting liquid are illustrated in figure Al.3.29 where the experunental pair correlation and structure factors for silicon are presented. The radial distribution function shows a sharp first peak followed by oscillations. The structure in the radial distribution fiinction reflects some local ordering. The nature and degree of this order depends on the chemical nature of the liquid state. For example, semiconductor liquids are especially interesting in this sense as they are believed to retain covalent bonding characteristics even in the melt. 

The most connnonly used detector in EPR is a semiconducting silicon crystal in contact with a tungsten wire, which acts as an MW rectifier. At microwatt powers, crystal detectors are typically non-linear and render a... 

Semiconductors may also be made from a maferial which is normally an insulator by infroducing an impurify, a process known as doping. Figure 9.9 shows fwo ways in which an impurify may promote semiconducting properties. In Figure 9.9(a) fhe dopanf has one more valence election per atom fhan fhe hosf and confribufes a band of filled impurify levels 1 close to fhe conduction band of fhe hosf. This characterizes an n-fype semiconductor. An example is silicon (KL3s 3p ) doped wifh phosphoms (KL3s 3p ), which reduces fhe band gap to abouf 0.05 eY Since kT af room femperafure is abouf 0.025 eY the phosphoms... 

Semiconducting devices, switches and miniaturised v.h.f. circuits are all particularly sensitive to the slightest reaction on critical surfaces, and in devices calling for the highest levels of reliability even the most inert of the phenolic, epoxide and silicone resins are not considered to be fully acceptablecorrosion of electronic assemblies may often be enhanced by migration of ions to sensitive areas under applied potentials, and by local heating effects associated with current flows. 

Gallium arsenide is a semiconducting material. If we wish to modify the sample by replacing a small amount of the arsenic with an element to produce an n-type semiconductor, which element would we choose selenium, phosphorus, or silicon Why ... 

Bocarsly AB, Bookbinder DS, Dominey RN, Lewis NS, Wrighton MS (1980) Photoreduction at illuminated p-type semiconducting silicon photoelectrodes. Evidence for Fermi level pinning. J Am Chem Soc 102 3683-3688... 

Miller et al. (1996) give examples of APFIM studies of the surface oxides formed on silicon, and studies of the stoichiometry of thermal oxide layers of this element, as well as a wide range of binary III-IV semiconducting materials. 

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. 

As described earlier, the covalently bonded hydrogen, by passivating dangling bond defects and removing strained weak Si—Si bonds from the network, dramatically improves the semiconducting quality of amorphous silicon. Hence without the presence of hydrogen, effective amorphous semiconductor devices such as solar cells or thin film transistors would not be possible. Unfortunately, low defect density, high electronic quality... 

Amorphous selenium glasses, semiconductivity in, 12 587 Amorphous semiconductors, 22 127-141. See also Amorphous silicon (a-Si) amorphous silicon growth for,... 

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