Effect of group II impurity and group III native defect on disordering Cu–Pt type ordered structures in In0.5(AlxGa1−x)0.5P layers

Abstract

Cu–Pt ordering is studied with cross-sectional transmission electron microscopy in p-type, n-type, and nominally undoped InAlP and In(AlGa)P layers. These different doping conditions allow us to investigate the effect of acceptor doping with magnesium and donor doping with tellurium on removing Cu–Pt ordering in In(AlGa)P. Even more significant, however, is the ability to investigate the effect of native group III self-diffusion in p-type, n-type, and nominally undoped InAlP and In(AlGa)P layers. Our data indicate that the rapidly diffusing Mg acceptor species is less effective on removing Cu–Pt ordering than the relatively slow diffusing Te donor species. Also, our results indicate that the native group III defects and group III self-diffusion play a more important role in removing Cu–Pt ordering than either group II acceptor diffusion or group VI donor diffusion.