Zn_（1－x）Mg_xS_ySe_（1－y）四元半导体合金的拉曼散射光谱研究

Raman Spectra of Zn_(1-x)Mg_xS_ySe_(1-y)Puaternary Alloys

用分子束外延方法在ＧａＡｓ（１００）衬底上生长了Ｚｎ１－ｘＭｇｘＳｙＳｅ１－ｙ四元半导体合金薄膜．用Ｘ－射线衍射方法确定了外延层的结构和晶格常数．测量了这些样品在平行和垂直两种不同几何配置下的拉曼散射光谱并对其特性做了研究。从实验上观察到了四类不同的晶格振动模：类ＺｎＳｅ的ＴＯ和ＬＯ模以及类ＺｎＳ和类ＭｇＳ的ＬＯ模，实验发现：在ＺｎＳｅ和ＺｎＳＳｅ中加入Ｍｇ使得类ＺｎＳｅ的ＴＯ和ＬＯ模的振动频率下降；同时，也使类ＺｎＳ模的频率随Ｓ的增加率减小。

Semiconductor quaternary alloy films Zn1-x MgxSySe1-y have beengrown on GaAs(100) substrates by molecular beam epitaxy. The crystal structure and the lattice canstants were determined by X-Ray diffraction. The Raman spectra with both perpendicular and parallel scattering geometries were measured and their properties were analyzed. Four types of vibrationmodes from this alloy sytem were identified: ZnSe-like TO and LO modes,and ZnS-like and MgS-like LO modes. It was found that the inclusion of Mg into ZnSe and ZnSSe reduced the vibration freguencies of ZnSe-like TO and LO modes.The amount of increase in the freguency of the Ens-like mode with increasing S was also reduced.