Full-wafer mapping of total and ionized EL2 concentration in semi-insulating GaAs using infrared absorption

Publisher Website
Google Scholar
Abstract
By combining infrared absorption data taken at two different wavelengths in the spectral region in which the native deep donor EL2 absorbs in GaAs, it is possible to determine the distribution of the total EL2 concentration and its filled fraction across a semi-insulating GaAs substrate. The distributions of net shallow acceptor concentration and free-electron concentration can then be deduced. Full-wafer maps of these quantities for a semi-insulating GaAs wafer are displayed along with Hall effect measurements which confirm the patterns observed optically.