Characteristics of semiconductors:

1. The conductivity of semiconductors is between conductors and insulators, such as silicon, germanium, selenium, etc., and their resistivity is usually between.

Second, the semiconductor is widely used because its conductivity is significantly affected by doping, temperature and light.

3. If the pure semiconductor single crystal silicon has a resistivity at room temperature of approximately, if a small amount of impurities (such as phosphorus) is added at a ratio of 1 in 1 million, the resistivity drops sharply to almost 1 million . The fundamental reason why semiconductors have such properties lies in the particularity of semiconductor atomic structure.

Commonly used semiconductor materials are single crystal silicon (Si) and single crystal germanium (Ge). The so-called single crystal refers to the crystal in which the atoms in the whole crystal are neatly arranged according to a certain rule. Very pure single crystal semiconductors are called intrinsic semiconductors.