ZnO films with <110> orientation were grown on R-Al 2O 3 substrates by LP-MOCVD, and the growth temperature was optimized. The quality of crystal, surface morphology and optical characteristic of the samples were investigated by XRD, AFM and PL method. The experimental results show that the FWHM of the optimized sample is only 0.50°. Compared with that of the sample grown on C-Al 2O 3 material under the same conditions, the surface morphology of the first sample is denser and smooth, while the PL spectra indicate that the exciton emitting intensity of <110> oriented ZnO film in the ultraviolet range is lower. However, the deep-level emission related to the intrinsic defects disappears in the spectrum. All above indicate that the <110> oriented ZnO film is more suitable for fabrication of the film SAWF with a low loss and a high frequency than for fabrication of the emitting device in ultraviolet range.
用MOCVD方法在c面蓝宝石衬底上生长ZnO薄膜。生长前衬底表面进行预处理,观察不同表面预处理对ZnO薄膜质量的影响。测量氧化锌的XRD谱,观察表面预处理后对氧化锌薄膜结晶质量的影响。室温下用325 nm的He-Cd激光器作为激发源测量ZnO薄膜的紫外发光谱,观察表面处理后对ZnO薄膜发光特性的影响。用HL5500 Hall System分别对ZnO薄膜的电学特性进行了测试。得到了ZnO薄膜的电阻率和霍尔迁移率,并得到氧气气氛处理后电阻率变小,霍尔迁移率变大;氮气气氛射频处理后电阻率变大,霍尔迁移率变小的结果。
High-quality MgxZn1-xO thin films were grown on sapphire(0001 ) substrates with a ZnO buffer layer of different thicknesses by means of metal-organic chemical vapor deposition. Diethyl zinc, bis-cyclopentadienyl-Mg and oxygen were used as the precursor materials. The crystalline quality, surface morphologies and optical properties of the Mg, Zn1-xO films were investigated by X-ray diffraction, atomic force microscopy and photoluminescence spectrometry. It was shown that the quality of the MgxZn1-xO thin films depends on the thickness of the ZnO buffer layer and an Mg, Zn1-xO thin film with a ZnO buffer layer whose thickness was 20 nm exhibited the best crystal-quality, optical properties and a flat and dense surface.