Indium tellurides

Zinc sulfide, ZnS, sphalerite (zinc blende) zinc sulfide, ZnS, wurtzite zinc selenide, ZnSe zinc telluride, ZnTe, cubic zinc telluride, ZnTe, hexagonal zinc polonide, ZnPo zinc aluminum selenide, ZnAl2Se4 zinc indium selenide, ZnIn2Se4 zinc indium telluride, Znhi2Te4. 

Indium Telluride, ln2Tey mol wt 6]2.47. In 37.49%, Te 62.51%. Prcpn of black brittle crystals by double furnace technique Inuzuka, Sugaike, Proc. Japan. Acad. 30, 383 (1954), C.A. 49, 2922e (1955). 

The values bf the enthalpies of formation of gallium and indium tellurides and selenides, required in these calculations, were taken from [14—16]. 

X-ray diffraction patterns of the films showed peaks characteristic of the chalcopyrite copper indium selenide or copper indium telluride compounds. Auger spectra and depth profiles showed the expected signal plus some carbon and surface oxidation. The stoichiometry varied with depth. 

Mercury Telluride. Compounds of mercury with tellurium have gained importance as semiconductors with appHcations in infrared detection (9) and solar cells (10). The ratio of the components is varied, and other elements such as cadmium, zinc, and indium are added to modify the electronic characteristics. 

The telluride halides crystallize in monoclinic lattices, but only In-TeBr and InTel are isotypic 162). InTeCl forms a layer type of structure, as do InSCl and its analogs, but, owing to the size of the Te atom and the enhanced covalency of the In-Te bond, only a coordination number of 4 for indium is realized. The structure is built up of strongly distorted, InTesraCli/j tetrahedra that share the corners and edges occupied by Te atoms. The Cl atoms are coordinated to one tetrahedron each, and do not take part in the layer formation 324, 325). 

Antimony telluride films have been grown from antimony(III) and tellurium(IV) oxides.167 Antimony telluride films were stoichimetric and consisted of nanoscale particles of the size 100 nm. The films had a good crystallinity.167 Indium selenide films were grown from indium sulphate and selenium oxide precursors.168 The films consisted of large particles, 70 to 200 nm in diameter. The band gap was 1.73 eV.168... 

A number of companies are currently involved in thin-fllm photovoltaics [17], and low-cost multilayer thin-fllm amorphous silicon and CdTe (cadmium telluride) systems have already been installed in large numbers with efficiencies of the order of 10% and of about 80% output after 25 years of operation. Large-scale plants have been announced for the so-called CIS (cadmium indium selenide) and CGIS (copper gallium indium diselenide), technologies with production efficiencies in the range 12-13% and laboratory measurements up to 19.9% [18]. 

Various inorganic semiconductors (p-type and/or n-type nonoxide semiconducting materials) sucb as amorphous or crystalline silicon (a-Si or c-Si), gallium arsenide (GaAs), cadmium telluride (CdTe), gallium phosphide (GaP), indium phosphide (InP), copper... 

Ellis AB, Bolts JM, Wrighton MS (1977) Characterization of n-type semiconducting indium phosphide photoelectrodes stabilization to photoanodic dissolution in aqueous solutions of telluride and ditelluride ions. J Electrochem Soc 124 1603-1607... 

Still another method used to produce PV cells is provided by thin-film technologies. Thin films are made by depositing semiconductor materials on a solid substrate such as glass or metal sheet. Among the wide variety of thin-film materials under development are amorphous silicon, polycrystalline silicon, copper indium diselenide, and cadmium telluride. Additionally, development of multijunction thin-film PV cells is being explored. These cells use multiple layers of thin-film silicon alloys or other semiconductors tailored to respond to specific portions of the light spectrum. 

Indium antimonide/Mercury cadmium telluride (InSb/MCT) sandwich. IR filters ... 

Although conventional solar cells based on silicon are produced from abundant raw materials, the high-temperature fabrication routes to single-crystal and polycrystalline silicon are energy intensive and expensive. The search for alternative solar cells has therefore focused on thin films composed of amorphous silicon and on other semiconductor heterojunction cells (e.g., cadmium telluride and copper indium... 

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