NONCONTACT, NO WAFER PREPARATION DEEP LEVEL TRANSIENT SPECTROSCOPY BASED ON SURFACE PHOTOVOLTAGE

We discuss a novel approach to Deep Level Transient Spectroscopy (DLTS) in which the emission of trapped minority carriers is analyzed employing the surface photovoltage (SPV) transient as measured in a non-contact manner on the native depletion barrier on semiconductor surfaces. Optical excitation is used as the trap-filling pulse. Experiments done on n-type GaAs demonstrate that the SPV-DLTS is suitable for wafer-scale, non-contact determination of deep level defects on semiconductor surfaces. The SPV approach can monitor emission rates up to 10(6) s-1 which is 10(2) to 10(3) above the limit of standard capacitance DLTS. The sensitivity of the method is comparable to that of the optical capacitance DLTS.