Deep energy levels that were caused by the high-energy low-dose proton bombardment of n-type or p-type material were investigated. Computer simulations were used to obtain the correct numbers of injected charge carriers which were needed for the evaluation of minority carrier capture data. On the basis of the measurements, it was possible to deduce the charge carrier lifetime profiles for proton irradiated n-type material under various conditions of injection concentration and temperature. At room temperature, and for low injection levels, it was found that the singly negative di-vacancy level, with a band-gap enthalpy of 0.421eV had the greatest effect upon the lifetime. At high injection levels, the vacancy-O center (0.164eV) was mainly responsible for the lifetime reduction.

A.Hallén, N.Keskitalo, F.Masszi, V.Nágl: Journal of Applied Physics, 1996, 79[8], 3906-14