Radiation effects in light emitting diodes, laser diodes, photodiodes, and optocouplers

Abstract

A variety of commercially available LEDs, LDs, PDs, and optocouplers from two German manufacturers were irradiated at a flash X-ray source, a 6oCo gamma ray source, and a 14 MeV neutron generator. Light output and emission spectrum of the LEDs and LDs were measured before and after irradiation at the 6oCo source. With the PDs we measured the dark current and the photo current before and after 6oCo irradiation. Determination of the sensitivity against neutrons was made off-line. With PDs we measured the photo current induced by pulsed X-rays. The GaAs LED showed a maximum decrease of output power of 28 dB after a total gamma dose of lo6 Gy and LDs a threshold current shift of 80% after neutron fluences of 4 * 1014 cm-2 (1 MeV).

Proton damage in linear and digital optocouplers

“…Later work in the laboratory showed that the failures were due to extreme sensitivity of LEDs within the optocouplers to displacement damage from protons [1-3]. Although earlier work had been done on displacement damage in lightemitting diodes, none of the devices studied previously had been heavily damaged at the low radiation levels where the optocouplers failed in space [4][5][6][7]. Subsequent work has shown that LED damage varies over an extremely wide range, depending on the particular manufacturing technology.…”

LED Technologies for Optocouplers: Fundamental Issues and Hardness Assurance

“…This property causes this type of LED to be extremely sensitive to displacement damage, despite the high light emitting efficiency. Several publications have addressed the problem of displacement damage in amphoterically doped LEDs as well as in commercial optocouplers that use them [3]- [6], [10].…”

Research on Degradation of GaN-Based Blue LED Caused by γ Radiation under Low Bias

“…In particular, the 1/f noise has been found suitable for study of the physical mechanisms of degradation caused by radiation. It is shown that low-frequency noise characteristic investigation is a sensitive method for explaining quality and reliability problems of optoelectronic devices (laser and LEDs and photodetectors) [10][11][12][13][14]. e low-frequency noise level could be an important indicator of the LED's degradation caused by radiation.…”