Study On Radiation Damage Effects Of GD4N24R Optocouplers

Optocouplers are widely used in spacecraft communication systems due to their small size,long service life,strong anti-interference ability,and strong non-contact isolation.However,the charged particles in the space environment can cause damage to the devices.Therefore,research on optoelectronics The space radiation damage effect of the coupler has very important engineering and academic significance.In this paper,GD4N24 photoelectric coupler is selected as the experimental object,and 30 MeVSi ion,1MeV neutron and different dose rate γ-ray irradiation experiment are carried out.Combined with the 4200 semiconductor tester to test the electrical properties of the photoelectric coupler,the deep-level transient spectrum is used.Detect and analyze the defects generated in the optocoupler,explore the effects of different radiation sources on the performance of the optocoupler and the damage mechanism,and explore the equivalence of the displacement damage of SI ions and neutrons through simulation software such as SRIM and GEANT4.The experimental results show that under 30 MeVSi ion irradiation,the electrical performance and current transmission ratio of the photocoupler are significantly reduced,the performance of the light-emitting diode in the discrete device is almost unaffected,and the current gain of the phototransistor is degraded.As the irradiation fluence increases,the electrical performance of photocouplers and phototransistors gradually declines.Through comparative experiments of hydrogen immersion pretreatment,it is found that hydrogen can aggravate the degradation of photocoupler performance.Combined with deep-level transient spectroscopy analysis,SI ion irradiation produces different types of vacancy defects inside the phototransistor.The comparison shows that hydrogen passes through.Ionization defects aggravate the degradation of the performance of the optocoupler.1MeV neutron irradiation is similar to Si ion.The electrical performance of photocoupler and discrete device phototransistor is significantly reduced,and lightemitting diodes have good radiation resistance due to their double heterojunction structure,and the IV characteristics hardly occur.Variety.Neutron irradiation produces deep energy level displacement defects in the phototransistor,which affects the trapping and recombination of carriers.The excess base current increases,the current gain decreases,and the performance of the phototransistor decreases,which leads to the degradation of the performance of the photocoupler.The experimental results of γ-ray irradiation with different dose rates show that the performance of the photocoupler has been slightly degraded.Combined with the deeplevel transient spectrum,it is found that γ-rays have produced oxide charge defects in the phototransistor,indicating that the photocoupler has an effect on ionization defects The sensitivity is lower than displacement damage.The equivalence study shows that30 MeVSi ions and 1MeV neutrons produce different types of defects inside the phototransistor.The calculation shows that the displacement damage of Si ions and neutrons cannot be equivalent.