Although times have changed, the Schottky barrier diode remains an important component in many systems because of its unique features.
The discussion will first focus on the origin of the energy bands and their relationship to the Fermi level. The simple theory is later modified by the barrier‐lowering effect and the presence of surface states. The reverse bias depletion capacitance and, subsequently, the forward current characteristics are determined. Equivalent circuit models are discussed that are useful for circuit design. Finally, some comments are made about recent progress in wide bandgap Schottky barrier diodes. The applications sections emphasize mixer design, as this seems to be the predominant use of Schottky devices.