Some info about Semiconductors
A semiconductor material has an electrical conductivity value falling between that of a conductor such as copper, and an insulator such as glass. Semiconductors are the foundation of modern electronics. Semiconducting materials exist in two types - elemental materials and compound materials. The modern understanding of the properties of a semiconductor relies on quantum physics to explain the movement of electrons and holes in a crystal lattice. The electrical conductivity of a semiconductor material increases with increasing temperature, which is behavior opposite to that of a metal. semiconductor devices can display a range of useful properties such as passing current more easily in one direction than the other, showing variable resistance, and sensitivity to light or heat.
Learn Physics: Types of Semiconductors