Gamma and neutron irradiation of optoelectronic devices

Abstract

Active optoelectronic devices such as light emitting diodes (LEDs), laser diodes (LDs), and photodiodes (PDs) were evaluated for degradation under gamma and 14 MeV neutron irradiation. Total dose values and neutron fluences were chosen in such a way that we get estimates of the behaviour especially in space environments and nuclear engineering. The devices are designed for wavelengths from visible (450 nm) to infrared (1300 nm). LEDs and LDs show a reduction of light output power and LDs also a shift of threshold current after irradiation. With the LEDs we also measured the light power distribution on the chip surface. Irradiations of PDs with /sup 60/Co gammas up to a total dose of 10/sup 6/ Gy as well as irradiations with neutrons up to fluences of 3/spl times/10/sup 1/3 cm/sup -2/(1 MeV) lead to a strong increase of dark current.