New method to determine the photoionization threshold energy of a deep level from photocapacitance

摘要

A new method is proposed to determine the photoionization threshold energy of a deep level from the dependence of photocapacitance on the scanning rate of light wavelengths. The validity is demonstrated by applying this method to minority carrier traps in annhyphen;type GaAs and aphyphen;type GaP. It is shown that Lucovsky's model of photoionization cross section is valid at least in photon energies less than 1.5 times the threshold energy.