MULTI-BANDGAP DUAL FUNCTION LIGHT EMITTING/DETECTING DIODE

摘要

This invention relates to a semiconductor diode device (65) capable of performing the dual functions of emission and detection of optical signals. The diode can be used in a bi-directional optical communication link where the diode alternates between transmitting and receiving optical signals. This simplifies the structure and lowers the cost as compared to conventional links where separate diodes are used as emitters and detectors. In particular, this invention relates to a structure of a light emitting diode for emission (52) and a photodiode for detection (53). The invention is a semiconductor p-n junction single heterostructure diode (65) which can operate efficiently as a light emitting diode (LED) when a forward bias voltage is applied and as a light detecting photodiode when a zero or small reverse bias voltage is applied.