25 - Semiconductors

a substance whose resistivity is between that of a good conductor and a good insulator.

Positively charged gaps or spaces

Which are created when an electron breaks free

From a covalent bond

The movement of charges through a pure semiconductor

With an equal number of electrons and holes

the addition of impurities in a semiconductor

to increase its conductivity

A semiconductor

whose resistance decreases rapidly with increasing temperature.

a semiconductor whose conductivity

is increased when light shines on it.

A semiconductor in which electrons

are the majority charge carriers

a semiconductor in which positive holes

are the majority charge carriers

The movement of charges

through a doped semiconductor

with an unequal number of electrons and holes

The region connecting

a P-type semiconductor to an N-type semiconductor

the region at both sides of a P-N
junction

that contains no free majority charge carriers

*The p.d. that exists across a p-n junction

caused by holes and electrons moving across the junction

when it was formed

**Check asterisk**

*A forward biased p-n junction conducts current.
A reverse biased p-n junction does not conduct current.

**Check asterisk**

A device that allows current to flow in one direction only

A device that converts A.C. to D.C.