Changes in 8-12 gm Cd_xHg_(1-x)Te photodiode arrays caused by fastneutron irradiation

摘要

We have measured the current-voltage characteristics of the long-wavelength infrared (LWIR) photodiode array, formed on the epitaxial Cd_xHg_(1-x)Te film (x = 0.21-0.23) with a high concentration of the Shockley-Read-Hall centres, before and after irradiating it with fast neutrons (energy 1 MeV, dose 5 x10~(13) cm~(-2)) at room temperature. Residual changes in current-voltage characteristics, persisting after 20 days, have been identified. Model calculations indicate that the Shockley-Read-Hall centre concentration increases 2-4 times, and the carrier lifetime decreases 2-5 times after the irradiation.