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CH1012
SEMICONDUCTORS
A semiconductor conducts
(electricity) and the conductivity
increases with temperature.
There are two main types of semiconductors:
There are two main types of semiconductors:
1. Intrinsic - naturally occurring
eg.
Si, Ge.
- empty conduction band - filled
valence
band
2. Extrinsic
- May be an insulator or intrinsic semiconductor
where the conductivity
is controlled by adding
small amounts of
impurities called
dopants to the solid
to increase the
number of mobile
charge carriers.
- May be an insulator or intrinsic semiconductor
where the conductivity
is controlled by adding
small amounts of
impurities called
dopants to the solid
to increase the
number of mobile
charge carriers.
