NEUTRON TRANSMUTATION DOPING AS AN EXPERIMENTAL PROBE FOR AS-SE IN ZNSE

An experimental investigation of the effects of isolated arsenic atoms at substitutional selenium sites in ZnSe is presented. Two methods em ploying neutron transmutation doping and utilizing the long half-life of Se-75 to introduce As-Se dopants in ZnSe are described. In the firs t method, bulk ZnSe is neutron irradiated and then annealed before sig nificant decay of Se-75 occurs. In the second method, a post-neutron-i rradiation homoepitaxial crystal-growth technique is used where the As -75 decay product is incorporated in an epitaxial layer of ZnSe after the epitaxial layer is grown. Since the nuclear recoils associated wit h the decay of Se-75 to As-75 are too small to displace the arsenic at oms from their selenium sites, arsenic doping at selenium sites is ens ured.