Photoluminescence Properties of Nitrogen-Doped ZnSe Films Grown by Low-Pressure MOVPE

Abstract
Nitrogen-doped ZnSe layers were grown on (100) GaAs by low-pressure MOVPE using dimethylzinc and hydrogenselenide as reactants. Ammonia was used as a dopant source. The ZnSe films were characterized mainly by measuring photoluminescence at low temperatures, where ammonia-gas flow rate was changed. It has been reconfirmed that nitrogens can be incorporated into ZnSe as shallow acceptors with activation energy of about 100–110 meV. However, in heavily doped ZnSe films, it has been found that the nitrogens are no longer shallow acceptors, but deep centers associated with Y lines, and other types of deep centers are introduced.