Radiant energy optical detector amplifier

Abstract

Abstract A semiconductor device of certain p-type materials, such as indium antimonide (InSb), is capable of impact ionization initiated by injection of electrons if maintained within a certain temperature range, e.g., 50*- 120* K. A long npp+ InSb diode is maintained in a controlled temperature environment at 77*K. An external biasing source reverse biases the diode''s p+-p junction to block injection of electrons from the source and creates a relatively high electric field within the diode. When electrons are optically injected into the cathode end of the diode adjacent the p+-p junction by, for example, exposing the cathode region to infrared radiation, they initiate an impact ionization wave which travels the length of the diode in the very short time. When the impact ionization wave reaches the diode''s anode, the resultant current through the diode is many times higher than the current initiated by the photoelectric effect without impact ionization. This current is used to signify fast detection of infrared radiation in small quantities and may also be used, in conjunction with the known applied electric field, to indicate the amount of incident radiation.

Inventors

• 👤 Johnson B Ancker

Bibliographic Details