Optical and magneto-optical determination of the EL2 concentrations in semi-insulating GaAs

Abstract
A comparison is presented of two different optical methods to determine the concentrations of both charge states of EL2 defects. It is shown that a discrepancy exists for published optical cross sections and that optical absorption measurements are not suitable to determine the concentrations of the ionized EL2 defects with sufficient precision in semi-insulating GaAs wafers.