The measurement of minority carrier diffusion lengths for high purity GaAs, using an electron beam induced current technique

Abstract

Measurements of minority carrier diffusion lengths for p-type and n-type GaAs were carried out using an electron beam induced current technique. The GaAs material was grown by liquid phase epitaxy at the Australian Nuclear Science and Technology Organisation. The diffusion lengths measured for the n-type materials show good agreement with past results for material of similar purity. For higher purity p-type and n-type samples, diffusion lengths were observed which are larger than any previously reported. For different electron beam voltages the observed values of diffusion length were unaffected by surface recombination. This again indicates very pure material. The diffusion length measurements reported here indicate that the LPE GaAs samples being produced by the Australian Nuclear Science and Technology Organisation's Radiation Detectors Project are of the highest quality for producing X-rays and low energy gamma ray radiation detectors. 20 refs., 2 tabs., 4 figs