Growth of (1 0 0), (0 1 0) and (0 0 1) β-Ga2O3 single crystals by vertical Bridgman method

Growth of β-Ga2O3 single crystals with three growth orientations perpendicular to the (1 0 0), (0 1 0) and (0 0 1) planes was investigated by the vertical Bridgman (VB) method. Three kinds of seed crystals with different orientations were prepared, and crystals with a diameter of 1 in. were obtained under the same growth conditions. Examination by crossed polarizer and X-ray topography shows that the three ingots were twin-free single crystals. For (1 0 0), (0 1 0) and (0 0 1) plane wafers, selective etching using H3PO4 was conducted, then different etching rates due to the anisotropy of β-Ga2O3 were determined and specifically shaped etch pits were also revealed. Line-shaped defects extending in the [0 1 0] direction were observed in the (1 0 0), (0 1 0) and (0 0 1) grown crystals.