Study of electric field enhanced emission of deep levels using a new emission spectroscopic technique

A small capture pulse followed by an emission pulse was used to study the carrier emission of defect centers in the presence of electric field. The capture pulse is used to fill a localized group of centers with electrons in n-type semiconductors and a reverse pulse causes these centers to emit electrons at an electric field determined by the reverse-bias pulse. The enhancement of the emission due to the presence of a high electric field can be determined readily from the change of capacitance transients detected using a conventional deep level transient spectroscopy setup. In this technique, a low dc bias is used during the measurement of the capacitance transients and thus results in a high sensitivity of detection. Calculation and experimental results are given for the E_c -0.35 eV center in GaAs.