T Kudou

Impact of neutron irradiation on optical performance of InGaAsP laser diodes

Abstract Results are presented of an extended study on the degradation and recovery behavior of optical and electrical performance and on induced lattice defects of 1.3 μm InGaAsP double channel planar buried heterostructure laser diodes with an In 0.76 Ga 0.24 As 0.55 P 0.45 multi-quantum well active region, subjected to a 1 MeV fast neutron and 1 MeV electron irradiation. The degradation of the device performance increases with increasing fluence. Two hole capture traps with near midgap energy level in the In 0.76 Ga 0.24 As 0.55 P 0.45 multi-quantum well active region are observed after a 1×10 16 n/cm 2 irradiation. These deep levels are thought to be associated with a Ga vacancy. The decrease of optical power is related to the induced lattice defects, leading to a reduction of the non-radiative recombination lifetime and of the carrier mobility due to scattering. The difference in radiation damage between 1 MeV fast neutrons and 1 MeV electrons is discussed taking into account the non-ionizing energy loss (NIEL). The radiation source dependence of performance degradation is attributed to the difference of mass and the probability of nuclear collision for the formation of lattice defects. The decreased optical power recovers by thermal annealing, and the recovery increases with increasing annealing temperature. The optical power recovers by 45% for 1 MeV neutron irradiation with a fluence of 1×10 15 n/cm 2 after a 300°C annealing.

Impact of induced lattice defects on performance degradation of AlGaAs/GaAs p-HEMTs

Abstract Irradiation damage and its recovery behavior resulting from thermal annealing in AlGaAs/GaAs pseudomorphic HEMTs, subjected to 1-MeV electrons, 1-MeV fast neutrons and 220-MeV carbon, are studied. The drain current and effective mobility decrease after irradiation, while the threshold voltage increases in positive direction. The decrease of the mobility is thought to be due to the scattering of channel electrons with the induced lattice defects and also to the decrease of the electron density in the two-dimensional electron gas (2DEG) region.

Degradation of InGaAs pin photodiodes by neutron irradiation

Irradiation damage in p - i - n photodiodes by 1 MeV fast neutrons is studied as a function of fluence for the first time. The degradation of the electrical and optical performance of diodes increases with increasing fluence. The influence of the radiation source on device degradation is then discussed by comparison with 1 MeV electrons with respect to the numbers of knock-on atoms and the non-ionizing energy loss (NIEL). The dependence of performance degradation on the radiation source is attributed to the difference of mass and the probability of nuclear collision for the formation of lattice defects.

Radiation damage of InGaAs photodiodes by high energy particles

Results are presented of a study on the performance degradation and the induced lattice defects of In{sub 0.53}Ga{sub 0.47}As p-i-n photodiodes, subjected to 220-MeV carbon particles. The effects on both the dark current and the photo-current are investigated as a function of the carbon fluence and correlated with DLTS results. The device degradation is compared with the one observed after exposure to 1-MeV electrons, 1-MeV fast neutrons and 20-MeV alpha rays, respectively. The differences in damage coefficients will be explained in view of the calculated number of knock-on atoms and the nonionizing energy loss (NIEL). The recovery behavior of the diode performance and of the induced deep levels by isochronal annealing is also reported.

Effect of irradiation in InGaAs photo devices

Results are presented of an extended study on the degradation of electrical and optical performance and the induced lattice defects of In0.53Ga0.47As p-i-n photodiodes, subjected to a 20 MeV alpha-ray irradiation. The difference in radiation damage with 1 MeV fast neutrons and 1 MeV electrons is discussed taking into account the energy transfer. The radiation source dependence of performance degradation is attributed to the difference of mass and the probability of nuclear collision for the formation of lattice defects.

Radiation damage of In0.53Ga0.47As photodiodes by high energy particles

The performance degradation of In0.53Ga0.47As p-i-n photodiodes, subjected to a 220-MeV carbon particle irradiation in the fluence range 1010 to 1013 cm−2, is reported. It is shown that the increase of the dark current scales roughly with the displacement damage created in the n-type InGaAs region. The degradation of the photo-current, on the other hand, does not scale with the displacement damage, for all irradiations studied. Therefore, it is believed that the photo-current suffers from increased surface recombination, which is related to the ionization damage created in the passivation layer.

Radiation source dependence of degradation and recovery of irradiated In/sub 0.53/Ga/sub 0.47/As PIN photodiodes

Irradiation damage and its recovery behavior resulting from thermal annealing in In/sub 0.53/Ga/sub 0.47/As PIN photodiodes, subjected to a 20-MeV alpha ray, are studied. The degradation of the electrical and optical performance of diodes increases with increasing fluence. In the In/sub 0.53/Ga/sub 0.47/As epitaxial layers, hole and electron capture levels are induced by irradiation. The influence of the radiation source on the degradation and recovery is then discussed by comparison to 1-MeV electrons and 1-MeV fast neutrons with respect to the numbers of knock-on atoms and the nonionizing energy loss (NIEL). Isochronal thermal annealing for temperatures ranging from 75 to 300/spl deg/C shows that the device performance degraded by the irradiation recovers by thermal annealing, and that the recovery behavior has a radiation source dependence. The recovery increases with increasing annealing temperature. The amount of recovery for alpha rays is nearly the same as for neutron irradiation, while that for electron irradiation is much larger. The radiation source dependence of performance degradation is attributed to the difference of mass and the probability of nuclear collision for the formation of lattice defects.