High-mobility electronic transport in ZnO thin films

A systematic study of electronic transport properties was carried out for ZnO thin films grown on high-temperature annealed buffer layers of semi-insulating Mg0.15 Zn0.85 O. As functions of growth temperature and oxygen pressure during laser molecular-beam epitaxy growth, there can be seen optimum growth conditions where gross concentration of intrinsic defects is thought to be reduced. For the best qualified film, Hall mobilities of 5000 cm2 V-1 s-1 at 100 K and 440 cm2 V-1 s-1 at 300 K were recorded with the residual electron densities of 4× 1014 and 9× 1015 cm-3, respectively.