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Germanium (Ge) and SiC |
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Germanium was almost "useless" but is experiencing some comeback now
(2007) in conjunction with Si technology. | |
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SiC is very difficult to obtain as a good single crystal (many polytypes) but has some
desirable properties for high speed or high power devices | |
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II-Vl semiconductors are objects of heavy research but hardly used for
products at present. | |
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The only used material is CdTe for solar cells that are actually on the market. We
might see, maybe, ZnO being used for LED's in the future. |
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"Chalcogenides", meaning compounds with "Chalcogens", i.e.
S, Se, and Te as major elements, are often semiconductors |
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Oxygen, in the same IIa group, forms "oxides"! |
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The most prominent representative of chalcogenides (besides CdTe) is "CIS"
(CuInSe2) or better "CIGS" (CuInxGa1-xSe2) used
for solar cells and actually on the market. | |
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Organic semiconductors. A relatively recent addition to the club, organic
semiconductors seem to have a bright future at least in optoelectronics |
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OLED's are on the market, in particular as part of a flat panel display; the first
OLED based TV screen has been announced for 2008. |
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The big problem of OLED's is their sensitivity to oxygen. |
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© H. Föll (Semiconductor Technology - Script)
