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Re: semi conductors



The main reason has to do with the number of charge carriers free to carry
current.

An insulator has hardly any free charge carriers.

A conductor has many free charge carriers (for example, copper and
aluminum have about 10^29 free electrons per cubic meter).

An intrinsic (pure) semiconductor has equal numbers of free electrons and
holes, many more than an insulator, but many fewer than a conductor. For
instance, at room temperature, pure germanium has about 10^19 per cubic
meter and pure silicon has about 10^16 per cubic meter.

Tom Sandin

On Thu, 18 Apr 2002, giustifamily wrote:

why has a pure semi conductor have an electrical conductivity between those
of insulators and conductors at room temperature?