Radiation effects in optoelectronic devices

Active optoelectronic devices such as light emitting diodes (LEDs), laser diodes (LDs), photodiodes (PDs), and optocouplers (OCs) were evaluated for degradation under gamma, 14 MeV neutron, and flash X-ray irradiation. Dose rates, total dose values, and neutron fluences were chosen such that we get estimates of the behavior especially in space environments and nuclear engineering. The devices are designed for wavelengths from 660 to 1550 nm. LEDs showed a decrease of output power between 0.1 and 28 dB after a total gamma does of 106 Gy or neutron fluences of 4 X 1014 cm-2 (1 MeV), respectively. The threshold current of LDs shifted to higher values with increasing dose (60Co) and neutron fluence. Irradiations of PDs with 60Co gammas up to a total dose of 106 Gy as well as irradiations with neutrons up to fluences of 4 X 1014 cm-2 (1 MeV) lead to a strong increase of dark current. OCs show a significant reduction of the current transfer ratio at dose values between 103 and 104 Gy. Except two types, the optocouplers did not survive neutron fluences >= 8 X 1011 cm-2 (1 MeV).