The role of threading dislocations and unintentionally incorporated impurities on the bulk electron conductivity of In-face InN

The origin of bulk electrons in In-face InN has been studied by considering the effects of both unintentionally incorporated impurities and threading dislocation densities on electron transport properties. The concentration of unintentionally incorporated oxygen and hydrogen scaled with the bulk electron concentration while threading dislocations had no discernable effect on the electron concentration. We conclude that unintentional impurities were the significant source of electrons and threading dislocations acted only as scattering centers limiting the electron mobility in as-grown InN films. Further, we present In-face InN growth techniques controlling the incorporation of oxygen and hydrogen and reducing threading dislocation densities.