Conductors, Insulators and Semi-Conductors: Junctions

Doping Germanium and Silicone cause them to behave in unusual but predictable ways when exposed to voltage, depending on which charge of the voltage is connected to which type of material (P or N).

The line along which joined P and N material meet is called the Junction  . A simple component consisting of P-material and N-material joined at a junction is called a diode. The application of voltage to the two doped semiconductor materials is called biasing.

A more complex material containing two PN junctions is called a Transistor  .