Effects of Homo-buffer Layer on Properties of Sputter-deposited ZnO Films

Two-step growth regimes were applied to realize a homoepitaxial growth of ZnO films on freestanding diamond substrates by radio-frequency(RF)reactive magnetron sputtering method.ZnO buer layers were deposited on freestanding diamond substrates at a low sputtering power of 50 W,and then ZnO main layers were prepared on this buffer layer at a high sputtering power of 150 W.For comparison,a sample was also deposited directly on freestanding diamond substrate at a power of 150 W.The effects of ZnO buffer layers...