InGaN薄膜的紫外共振喇曼散射  

Ultraviolet resonant Raman scattering in InGaN films

作　　者：王瑞敏[1] 陈光德[1] 

机构地区：[1]西安交通大学理学院大学物理部,西安710049

出　　处：《物理学报》2009年第2期1252-1256,共5页Acta Physica Sinica

基　　金：国家自然科学基金(批准号:10474078);陕西省自然科学基金(批准号:2004A01)资助的课题~~

摘　　要：利用325nm紫外光激发,对不同组分的InxGa1-xN薄膜的喇曼散射谱进行了研究.在光子能量大于带隙的情况下,观察到显著增强的二阶A1(LO)声子散射峰.二阶LO声子峰都从一阶LO声子的二倍处向高能方向移动,移动量随样品In组分的增加而增大,认为是带内Frhlich相互作用决定的多共振效应引起的.分析了一阶LO声子散射频率和峰型与In组分的关系.在喇曼谱中观察到样品存在相分离现象,并与X射线衍射的实验结果进行了对比.此外,还观察到位于1310cm-1附近的InxGa1-xN的E2声子组合模.Ultraviolet Raman scattering spectra of InxGa 1-x N films with different In compositions were investigated using 325 nm laser line. For photon energy above the energy gap, strong enhanced 2A1（LO）phonon scattering lines were observed. Four 2LO peaks shift from twice the energy of the first-order LO peak, to the high energy end and the shifts increase with In contents in the samples. It is attributed to the multiple resonance resulting from intraband-Frhlich interaction. The composition dependence of LO phonon mode frequency and line shape was analysed. The phase separation was observed in Raman spectra and compared with the data of X-ray diffraction. Furthermore, the E2 phonon combination mode of InxGa 1-x N was observed at about 1310 cm^ -1 .

关 键 词：InxGa1-xN合金 紫外共振喇曼散射 二阶声子 相分离 

分 类 号：TN304[电子电信—物理电子学]