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Compound semiconductors

  1. Nov 23, 2007 #1
    Which groups in the periodic system forms compounded semiconductors?

    Is it those who can share 8 valenceelectron together? or is it those who can share 4 valence electrons together?
    If this is the case why is it just those who can form compound semiconductors?
    Can i use the electronconfiguration to show this, or how should i motivate this?
    Also which type of bond is on those compounded semiconductors?
  2. jcsd
  3. Nov 23, 2007 #2
    This should probably be in the Atomic, Solid State, Comp. Physics forum.

    In order to have a semiconductor, the bonding in the material needs to be somewhere between covalent and metallic, and you can't have a large difference in electronegativity between the atoms involved. If you have strong covalent bonding (or strongly localized electrons) then this gives you a good insulator, like with diamond. If there is a large electronegativity difference, as in NaF, then you will get an ionic material which is an insulator.

    I don't think you can make an argument purely from an electron configuration standpoint; diamond and silicon both have the same configuration for their valence electrons, however diamond is a good insulator and silicon is a semiconductor.
  4. Nov 23, 2007 #3


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    There is a pretty simple "rule"; the average "group number" should be 4.
    E.g. silcon and germanium are in group IV. Most of the other important compounds are III-V compounds (i.e. (3+5e)/2), e.g. GaAs,GaN, InP are all widely used.
    There are also many II-VI semiconductors, although AFAIK only the zink- and cadmium compounds are actually used (e.g. ZnS).
    However, this "rule" does not always work, it does not cover for example the chalcopyrites.
  5. Nov 23, 2007 #4


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    Note: You can make hole doped chalcopyrites, which are semiconductors.
  6. Nov 24, 2007 #5

    Dr Transport

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    Yes they are, some chalcopyrites are also known as pseudo-III-V or pseudo-II-VI materials. (I did my doctorate in chalcopyrite optical and elactronic property calculations.)
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