Effects of Deep Centers on n-Type GaP Schottky Barriers

Abstract

Metal-n-type GaP barriers from 1.5 to 1.8 eV were obtained with Ag and Pt evaporated films. The barrier heights were measured using three different methods and found to be in agreement. The characteristics of the barriers were studied and the effect of deep centers on them investigated. Changes in capacitance in the dark and under illumination were studied and densities of centers present in the GaP crystals were measured. A deep center present in all of the crystals was detected and its cross section for electron capture was estimated. Hole-electron recombination currents were observed and investigated. The centers detected in these barriers could explain the characteristics and the measured hole-electron lifetime of ∼5×10−11 sec.