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本文报道了利用 MOCVD方法 ,在 Ga As衬底 ( 0 0 1 )面制备的立方 Ga N薄膜的光学性质 .利用光致发光 ( PL )光谱的半高宽确定制备的样品具有不同的晶体质量 .利用喇曼散射( RS)光谱研究了立方 Ga N薄膜中的光学声子模式 .横向 ( TO)和纵向 ( LO)声子在立方 Ga N中的散射峰分别位于 552 cm- 1和 739cm- 1.另外还观察到来自界面无序层的 TOB和 LOB.根据喇曼频移和选择定则可识别 Ga N中的相组成 .其来自六方相 Ga N的 E2 声子模 ,可作为识别立方 Ga N中六方相的标志 .随着退火温度的升高 ,样品中的界面层的效应减弱 ,六方相增加
In this paper, the optical properties of cubic GaN thin films prepared by the GaAs substrate (0 0 1) using MOCVD method have been reported. The samples prepared by PLF spectroscopy have different crystal masses. The optical phonon modes in cubic GaN films were investigated by Raman scattering (RS) spectroscopy, and the scattering peaks of the lateral (TO) and longitudinal (LO) phonons in the cubic Ga N are located at 552 cm-1 and 739 cm -1, respectively In addition, TOB and LOB from the interfacial disordered layer are also observed.The phase composition in Ga N can be identified according to the Raman shift and selection rules.The E2 phonon modes from the hexagonal phase Ga N can be used to identify the cubic Ga N hexagonal phase of the sign.With the annealing temperature increases, the effect of the interface layer in the sample weakened, the hexagonal phase increases