Semiconductor Avalanche Diode

a semiconductor diode at whose terminals the voltage remains nearly constant when the magnitude of the electric current through the diode varies within certain limits. The working region of the volt-ampere characteristic of such a diode lies in a narrow range of reverse voltages corresponding to the electrical breakdown of the diode’s p-n junction. At breakdown voltages U_br < 5 volts (V), the mechanism of the abrupt increase of current, or breakdown, is associated with the tunnel effect. When U_br > 6.5 V, the mechanism is associated with the avalanche multiplication of charge carriers. At intermediate voltages, the charge carriers initially generated as a result of the tunnel effect create the conditions necessary for a controllable avalanche breakdown.

In the USSR in 1975 silicon semiconductor avalanche diodes were manufactured for various rated stabilization voltages from 3 to 180 V. Semiconductor avalanche diodes are used to stabilize voltage and limit pulse amplitude. They are also used as sources of reference voltages and in potentiometric devices.