Chinese Acad Sci, Shanghai Inst Opt & Fine Mech, Shanghai 201800, Peoples R China
; Nanjing Univ, Natl Key Lab Solid State Struct & Phys, Nanjing 210008, Peoples R China
; Chinese Acad Sci, Beijing Inst High Energy Phys, Beijing, Peoples R China
We report Czochralski growth of LiGaO2 single crystals, which are promising substrate materials for the epitaxy of GaN since the lattice mismatch between LiGaO2 and GaN is only 0.9%. The dislocation etching pits morphologies and distribution characteristics were well revealed by chemical etching technique. Transmission electron microscopy (TEM) observations showed that gamma-Ga2O3 inclusions tended to emerge in LiGaO2 crystals owing to the volatilization of Li2O during growth process. Therefore, many edged dislocations were induced, which usually lie on (001) plane. The amount of gamma-Ga2O3 inclusions is closely related to growth parameters. X-ray topography shows that an interface parallel to (001) tends to form in the LiGaO2 crystals pulled along (100). The two parts aside the (001) interface were slightly rotated around the interface normal. The crystal quality can be improved by using starting materials with excess of Li2CO3 and adopting appropriate growth parameters. (C) 2000 Elsevier Science B.V. All rights reserved.