The diffusion of Ga in single crystals, implanted at 150keV to a dose of 2 x 1016/cm2 at 800 to 900C, was investigated using experimentally measured and simulated profiles. The Ga concentration profiles exhibited a characteristic tail, with a constant-concentration region arising from a Fermi-level effect upon diffusion. The Ga concentration profiles were compared with simulated profiles, and were found to be in good agreement. The simulation thus revealed possible models for Ga-diffusion, based upon the interstitialcy or vacancy mechanism.

Diffusion Model of Gallium in Single-Crystal ZnO Proposed from Analysis of Concentration-Dependent Profiles Based on the Fermi-Level Effect. T.Nakagawa, I.Sakaguchi, M.Uematsu, Y.Sato, N.Ohashi, H.Haneda, Y.Ikuhara: Japanese Journal of Applied Physics, 2007, 46[7A], 4099-101