PHOTOLUMINESCENCE OF MG-ION IMPLANTATION IN LOW-TEMPERATURE-GROWN GAAS

Photoluminescence properties of Mg-ion implanted layers of low-tempera ture (179-400-degrees-C) grown molecular beam epitaxial GaAs are repor ted. The Mg incorporation into the Ga site mainly produces the Mg-rela ted donor-acceptor pair transition. The Mg incorporation depends stron gly on the growth temperature of the layers. Mg trapping at defect cen ters formed by the excess As increases exponentially with the increase of the reciprocal growth temperature and is the dominant mechanism fo r the failure of Mg to incorporate into the Ga site. The possibility o f the trapping center for Mg being the As(in)-related defect originati ng from As-rich growth of low temperature GaAs is discussed.