In插入层对硅衬底外延InN晶体质量和光学特性的影响

在Si（111）衬底上分别预沉积0，0.1，0.5，1 nm厚度的In插入层后，采用等离子辅助分子束外延法制备了纤锌矿结构的InN材料，结合X射线衍射（XRD）、扫描电子显微镜（SEM）、吸收谱及光致发光谱研究了不同厚度的In插入层对外延InN晶体质量和光学特性的影响。XRD和SEM的测试结果表明，在Si衬底上预沉积0.5 nm厚的In插入层有利于改善外延InN材料的形貌，提高材料的晶体质量。吸收谱和光致发光谱测试表明，0.5 nm厚In插入层对应的InN样品吸收边蓝移程度最小，光致发射谱半峰宽最窄，并且有最高的带边辐射复合发光效率。可见，引入适当厚度的InN插入层可以改善Si衬底上外延InN材料的晶体质量和光学特性。

Influence of Indium Interlayer on The Crystal and Optical Properties of InN Grown on Silicon Substrate

Indium interlayers with thickness of 0, 0.1, 0.5, 1 nm were deposited respectively before wurtzite InN was grown on silicon substrate by plasma-assisted molecular beam epitaxy (PA-MBE). X-ray diffraction (XRD) spectra, scanning electron microscope (SEM), absorption and photoluminescence (PL) spectra were adopted to analyze the influence of indium interlayer on the crystal and optical properties of InN. XRD and SEM results indicate that indium interlayer with the thickness of 0.5 nm can improve the morphology of InN epitaxial with larger crystalline grains and have a better crystal quality. Absorption and PL spectra show that the sample with 0.5 nm indium interlayer exhibits the smallest blue-shift of absorption edge, the narrowest FWHM of PL spectra and the best near-band-edge radiative recombination efficiency. In conclusion, indium interlayer with appropriate thickness does have a positive influence on the crystal and optical properties of InN grown on silicon substrate.