机构地区: 厦门大学物理与机电工程学院物理学系
出 处: 《功能材料与器件学报》 2000年第4期393-396,共4页
摘 要: 测量了室温下三元GaxIn1-xP (x =0 .48)和四元 (AlxGa1-x) 0 .51In0 .4 9P (x =0 .2 9)合金背散射配置下的喇曼光谱。三元GaxIn1-xP的喇曼谱表现为双模形式 ,在DALA带上叠加了FLA模 ,在有序样品中观察到了类GaP的TO1模和类InP的TO2 模 ,类GaP的LO1模和类InP的LO2 模的分裂 ,表示有序度的b a比从无序样品的 0 .40变化到有序样品的 0 .1 0 ,有序样品b a比的降低是由于TO1模和LO1模分裂的影响所造成的。四元 (AlxGa1-x) 0 .51In0 .4 9P为三模形式 ,观察到了双峰结构的FLA模 ,由于Al组分的影响 ,类GaP的LO模成了类InP的LO模的肩峰。所有模式与经验公式吻合得很好。 Raman scattering spectroscopy is applied to investigate the phonon modes in Ga xIn 1-x P (x=0.48) and (Al xGa 1-x ) 0.51 In 0.49 P (x=0.29) alloys in back scattering geometry. Two mode behavior in Ga xIn 1-x P is found. In Ga xIn 1-x P, the FLA is superimposed on the DALA band. In ordered samples, the GaP like TO 1 and the InP like TO 2 are observed.The splitting of LO 1(GaP like) and LO 2(InP like) are believed to be the superlattice effect of ordering. the b/a ratio ranges from 0.40(nominally disordered) to 0.10(ordered). The small b/a of ordered Ga xIn 1 x P is affected by the TO 1 mode and LO 2′ splitting of LO 1 mode. (Al xGa 1-x ) 0.51 In 0.49 P is characterized by its three mode behavior. the doubling of FLA is found. Due to the influence of Al composition, the GaP like LO mode becomes a shoulder of the InP like LO mode. All the phonon modes are consistent with the results of empirical expressions.