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采用MOCVD方法在GaN/α-Al2O3(0001)衬底上生长获得了InGaN合金薄膜。X射线衍射(XRD)谱仅观察到In-GaN(0002)和GaN(0002)的衍射峰,表明InGaN与GaN均具有单晶C向的六方纤锌矿结构,利用衍射角度计算出InxGa1-xN薄膜的合金In组分x范围为0.34≤x≤1。室温下拉曼散射光谱测量发现,该系列InxGa1-xN合金的A1(LO)与E2(high)声子模峰位随着In组分x的增加均向低波速移动,并且峰位随组分的关系满足单模模式的变化规律。变温(93～673K)测量的拉曼散射光谱显示,InGaN的A1(LO)模峰位随着测量温度的升高向低波速非线性地偏移,该现象是由于晶格热膨胀和格点的非简谐振动的温度效应共同作用引起的。
InGaN thin films were grown on GaN / α-Al2O3 (0001) substrates by MOCVD. Only the diffraction peaks of In-GaN (0002) and GaN (0002) were observed by X-ray diffraction (XRD), indicating that both InGaN and GaN have a hexagonal wurtzite structure with a single crystal C direction and the InxGa1-xN The alloy has an In composition x range of 0.34 ≦ x ≦ 1. Raman scattering measurements at room temperature showed that the peak shifts of A1 (LO) and E2 (high) phonons of InxGa1-xN alloys all moved toward low wave velocity with the increase of In composition x, Relationship to meet the single-mode mode of change. The Raman scattering spectra measured at variable temperature (93 ~ 673K) show that the peak of A1 (LO) mode of InGaN shifts nonlinearly to low wave velocity as the measured temperature increases. This phenomenon is attributed to the lattice expansion Non-harmonic vibration caused by the combined effect of temperature.