Growth and properties of Mg-doped in-polar InN films

Mg doping into In-polar InN layers for different Mg fluxes is performed on GaN templates by molecular beam epitaxy, and their electrical and optical properties are investigated. Mg concentration is linearly proportional to Mg-beam flux, indicating that the Mg-sticking coefficient is almost unity. With Mg doping, electron concentration decreases by the effect of carrier compensation, but it begins to increase with further increasing Mg flux because of Mg-related donorlike-defects formation. For the partially carrier-compensated Mg-doped InN, two photoluminescence peaks are observed; one is originated from free-to-acceptor emission with an acceptor activation energy of about 61 meV and the other is similar to the conventional band-to-band emission. (C) 2007 American Institute of Physics.