Acta Optica Sinica, Volume. 26, Issue 5, 773(2006)
Preparation of γ-LiAlO2 Layer on (11-20)Sapphire by Vapor Transport EquilibrationLiu Shiliang
In order to find a new substrate which can probably substitute the sapphire for GaN epitaxy, a single phase and polycrystalline γ-LiAlO2 layer has been prepared by vapor transport equilibration (VTE) for 48 hours at 1000 ℃, 1030 ℃, 1050 ℃, 1070 ℃ and 1100 ℃, respectively. X-ray diffraction (XRD) and scanning electronic microscope (SEM) have been used to characterize the phase, orientation and surface morphology. The results show that the preferred orientation of γ-LiAlO2 layer depends on temperature. The γ-LiAlO2 layer prepared at 1050 ℃ has a highly preferred [100] orientation. A biaxial tensile stress existing in (001) γ-LiAlO2 may contribute to the form of the preferred [100] orientation. The directional coherence of stripes on the surface of γ-LiAlO2 grains closely corresponds to the preferred orientation of γ-LiAlO2 layer. The above results indicate that the γ-LiAlO2/α-Al2O3 prepared by vapor transport equilibration under appropriate conditions probably provides a promising compound substrate which adapts to grow (1-100) GaN film.
Get Citation
Copy Citation Text
[in Chinese], [in Chinese], [in Chinese], [in Chinese], [in Chinese]. Preparation of γ-LiAlO2 Layer on (11-20)Sapphire by Vapor Transport EquilibrationLiu Shiliang[J]. Acta Optica Sinica, 2006, 26(5): 773