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利用微区Ｒａｍａｎ散射技术，对低压ＭＯＣＶＤ生长的不同Ａｌ组分的ＡｌｘＧａ１－ｘＮ薄膜（ｘ＝０，０．０７，０．１５）进行了背散射Ｚ（Ｘ，Ｘ）Ｚ－几何配制下的测量．Ａ１（ＬＯ）模式的声子频移随Ａｌ组分的变化关系为：ω（ＡｌｘＧａ１－ｘＮ）＝（１＋０．２２０ｘ）ω（ＧａＮ）．观察到了Ａ１（ＬＯ）模式由于空间相关效应引起的展宽．Ｅ２模式随Ａｌ组分的的增大产生的移动很微小，但趋于展宽．这被认为是Ｅ２模式的声子频移随Ａｌ组分的增加而增大与其受到的张应力导致的声子频移随Ａｌ组分的增加而减小共同作用的结果．在多种配置下，观察到了Ａｌ０．０７Ｇａ０．９３Ｎ薄膜的Ａ１（ＴＯ）模式、Ａ１（ＬＯ）模式、Ｅ１（ＴＯ）模式和Ｅ２模式．验证了ＡｌｘＧａ１－ｘＮ薄膜的Ｒａｍａｎ选择定则．表明ＡｌｘＧａ１－ｘＮ薄膜具有单模行为．
Using the Raman scattering technique, the AlxGa1-xN thin films (x = 0,0.07,0.15) with different Al compositions grown by low-pressure MOCVD were backscattered by the Z (X, X) measuring. The phonon frequency shift in A1 (LO) mode changes with Al composition as follows: ω (AlxGa1-xN) = (1 + 0.220x) ω (GaN). The A1 (LO) mode was observed to broaden due to spatially correlated effects. The E2 mode produces very little movement with increasing Al composition, but tends to broaden. It is considered that the phonon frequency shift of the E2 mode increases as the Al composition increases and the phonon frequency shift due to the tensile stress caused by the Al composition decreases as a result of the reduction of the Al composition. Under various configurations, A1 (TO) mode, A1 (LO) mode, E1 (TO) mode and E2 mode of Al0.07Ga0.93N films were observed. The Raman selection rules of AlxGa1-xN films were verified. It shows that AlxGa1-xN films have single-mode behavior.