Recombination in gallium phosphide via a deep state associated with nickel

Abstract
The properties of nickel in gallium phosphide are discussed in terms of its behaviour as a recombination centre. Although it possesses a large minority-carrier cross-section and is present in v.p.e. material in quite large concentrations, it is found to have a very low majority-carrier cross-section so that the recombination rate saturates at low excitation densities. Thus the centre is unlikely to be of importance in the recombination process in normal l.e.d. structures.