Electric and optical properties of the ’’Cu-red’’ center in ZnSe

Abstract

Emission and capture rates describing the optical and thermal transitions at the ’’Cu-red’’ center in ZnSe have been investigated using a modified photocapacitance technique. By keeping the depletion region of a Schottky diode constant during the measurements of transients highly compensated samples could be used, resulting in larger signals than previously possible. This permitted optical-emission rates for both electrons and holes to be measured with higher accuracy and in a broader temperature region than in previous investigations. The capture cross section of electrons σn was determined in the temperature range 77–200 K. σn increases with decreasing temperature and has a value of 1.4×10−19 cm2 at 77 K.