Gil B. Group Ⅲ Nitride Semiconductor Compounds [M]. Oxford: Clarendon, 1998:23-25.[2] Nakamura S, Fasol G. The Blue Laser Diode: the Complete Story [M]. New York: Springer, 2000:14-19.[3] Xing Bing, Cao Wenyu, Du Weimin. Temperature-dependent PL of InGaN/GaN multiple quantum wells with variable content of In [J]. Chin. J. Lumin. (发光学报), 2010, 31 (6):864-869 (in Chinese).[4] Gibart P. Metal organic vapour phase epitaxy of GaN and lateral overgrowth [J]. Rep.Prog. Phys., 2004, 67 (5):667-672.[5] Zhang Yuchao, Xing Zhigang, Ma Ziguang, et al. Threading dislocation density comparison between GaN grown on the patterned and conventional sapphire substrate by highresolution X-ray diffraction [J]. Science China: Physics, Mechanics & Astronomy, 2010, 53 (3):465-468.[6] Yun F, Moon Y T, Fu Y, et al. Efficacy of single and double SiNx interlayers on defect reduction in GaN overlayers grown by organometallic vapor-phase epitaxy [J]. J. Appl. Phys., 2005, 98 (12):123502-123509.[7] Sagar A, Feenstra R M, Inoki C K, et al. Dislocation density reduction in GaN using porous SiN interlayers [J]. Phys. Status Solidi.(a), 2005, 202 (5):722-726.[8] Moon Y T, Xie J, Liu C, et al. A study of the morphology of GaN seed layers on in situ deposited SixNy and its effect on properties of overgrown GaN epilayers [J]. J. Cryst. Growth, 2006, 291 (1):301-308.[9] Xie J, Ozgur U, Fu Y, et al. Low dislocation densities and long carrier lifetimes in GaN thin films grown on a SiNx nano-network [J]. Appl. Phys. Lett., 2007, 90 (4):041107-041109.[10] Xie J Q, Chevtchenko A S, Ozgur U, et al. Defect reduction in GaN epilayers grown by metal-organic chemical vapor deposition with in situ SiNx nanonetwork [J]. Appl. Phys. Lett., 2007, 90 (26):262112-262114.[11] Kappers M J, Datta R, Oliver R A, et al. Threading dislocation reduction in (0001) GaN thin films using SiNx interlayers [J]. J. Cryst. Growth, 2007, 300 (1):70-74.[12] Bchetnia A, Toure A, Lafford T A, et al. Effect of thickness on structural and electrical properties of GaN films grown on SiN-treated sapphire [J]. J. Cryst. Growth, 2007, 308 (2):283-289.[13] Hertkorn J, Lipski F, Bruckner P, et al. Process optimization for the effective reduction of threading dislocations in MOVPE grown GaN using in situ deposited SiNx masks [J]. J. Cryst. Growth, 2008, 310 (23):4867-4870.[14] Kim D K. Influence of a SiN mask on GaN layer by metalorganic chemical vapor deposition [J]. J. Mater. Sci.: Mater. Electron., 2008, 19 (5):471-475.[15] Fang Z L, Li S P, Li J C, et al. GaN on Si-rich SiNx-coated sapphire at different growth stages: The surface morphologies and optical properties [J]. Thin Solid Films, 2008, 516 (18):6344-6352.[16] Zheng X H, Chen H, Yan Z B, et al. Determination of twist angle of in-plane mosaic spread of GaN films by high-resolution X-ray diffraction [J]. J. Cryst. Growth, 2003, 255 (1-2):63-67.[17] Moram M A, Vickers M E. X-ray diffraction of Ⅲ-nitrides [J]. Rep. Prog. Phys., 2009, 72 (3):036502-1-40.[18] Harima H. Properties of GaN and related compounds studied by means of Raman scattering [J]. J. Phys.: Condens. Matter., 2002, 14 (38):R967-R993.[19] Viswanath A K, Lee J I, Yu S, et al. Photoluminescence studies of excitonic transitions in GaN epitaxial layers [J]. J. Appl. Phys., 1998, 84 (7):3848-3859.[20] Chen Yao, Jiang Yang, Xu Peiqiang, et al. Stress control in GaN grown on 6H-SiC by metalorganic chemical vapor deposition [J]. Chin. Phys. Lett., 2011, 28 (4):048101-048105.[21] Zhao G Y, Adachi M, Ishikawa H, et al. Growth of Si delta-doped GaN by metalorganic chemical-vapor deposition [J]. Appl. Phys. Lett., 2000, 77 (14):2195-2197.