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对在c面蓝宝石上用氢化物气相外延法(HVPE)生长的六方相纤锌矿结构的GaN膜中的应力进行了分析。高分辨X射线衍射(002)面和(102)面摇摆曲线扫描(半高宽数值分别为317和358角秒)表明生长的GaN膜具有较好的晶体质量。利用高分辨X射线衍射技术准确测量了制备的GaN膜的晶格常数,并计算得到GaN膜中面内双轴应变和面外双轴应变分别为3.37×10-4和-8.52×10-4,等静压应变为-7.61×10-5。拉曼光谱和激光光致发光谱测试表明HVPE-GaN外延膜具有较好的光学特性,利用拉曼光谱的E2模式特征峰和激光光致发光谱中近带边发射峰的频移定量计算了外延膜中的面内双轴压应力和等静压应力。两种方法得到的面内双轴压应力较为相符。
The stress in the GaN film of a hexagonal wurtzite structure grown by hydride vapor phase epitaxy (HVPE) on c-plane sapphire was analyzed. High-resolution X-ray diffraction (002) plane and (102) plane rocking curve scan (FWHM of 317 and 358 arc seconds, respectively) indicate that the grown GaN films have better crystal quality. The lattice constants of the as-prepared GaN films were accurately measured by high-resolution X-ray diffraction and the in-plane biaxial and in-plane biaxial strains were 3.37 × 10-4 and -8.52 × 10-4 , The isostatic strain is -7.61 × 10-5. Raman spectroscopy and laser photoluminescence spectroscopy showed that the HVPE-GaN epitaxial films have good optical properties. The E2 mode characteristic peaks in Raman spectrum and the frequency shift of near-band edge emission peak in laser photoluminescence spectra were calculated quantitatively In-plane biaxial and isostatic compressive stresses in epitaxial films. The in-plane biaxial compressive stress obtained by the two methods is more consistent.