The effects of room temperature 6 MeV electron irradiation on the donor concentration, deep trap spectra, and diffusion lengths of nonequilibrium charge carriers were studied for undoped n-GaN grown by hydride vapor phase epitaxy. Changes in these parameters begin at a threshold electron fluence of 5 × 1015 cm−2. The diffusion lengths after this fluence decrease by a factor of 3, accompanied by a drastic increase in the density of deep electron traps with the level near Ec – 1 eV. There is a strong correlation between the changes in the density of these traps and the diffusion length of irradiated n-GaN, indicating that these centers control the lifetime in radiation damaged n-GaN. This is in sharp contrast to the starting material, where the lifetimes are controlled by other deep electron traps at Ec – 0.56 eV. The concentration of the latter is not strongly affected by high energy electron irradiation.

We report a study on transformations in absorption and emission spectra of novel bismuth (Bi) doped hafnia-yttria-alumina-silicate fiber, which arise as the result of bombardment by high-energy (β) electrons. Among the featuring data obtained, we reveal substantial growth of 'active' Bi center content in the fiber core-glass with increasing βirradiation dosage, resulting in dose-dependent intensification of the resonant-absorption bands and enhancement of the emissive potential of the fiber in near-IR, inherent to these centers.

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The degradation of CMOS operational amplifiers with bipolar and CMOS input stage under the irradiation at different dose rates and temperatures is investigated. It is shown that such circuits can be susceptible to both enhanced low dose rate sensitivity and time-dependent effects that should be taken into account during radiation testing.