机构地区: 南京大学物理学院物理学系
出 处: 《Journal of Semiconductors》 2004年第1期48-51,共4页
摘 要: 采用光辐射加热低压金属有机化学气相淀积 (L P- MOCVD)方法在蓝宝石衬底上生长了高 P组分的 Ga N1 - x-Px 三元合金薄膜 ,通过喇曼光谱和红外反射谱技术研究了 Ga N1 - x Px 合金中 P掺杂所引入的振动模 .与非掺 P的Ga N相比 ,在 Ga N1 - x Px 合金的喇曼谱和红外反射谱中分别观测到了多个由 P所引入的振动模 ,文中将它们分别归因于 Ga- P键振动引起的准局域模、间隙模以及 Both Raman and infrared reflection spectra for a series of high P compositional GaN 1-xP x alloys grown by means of light-radiation heating,low-pressure metal-organic chemical vapor deposition are investigated.The Raman spectra of GaN 1-x-P x alloys,recorded in backscattering geometry,exhibit four new vibrational modes at 256,314,377,and 428cm -1 compared with an undoped GaN sample.Those modes are assigned to the so called quasi-local mode induced by P in GaN,disorder-activated scattering and gap modes related to the Ga-P bond vibrations,respectively.The frequency of the A 1(LO) mode is found to redshift,which is attributed to the effects of alloying and strain.The infrared reflectance spectra show another new mode near 630cm -1,which is associated with the E 2(TO) phonon mode that results from a random distribution of the P atoms in GaN 1-xP x alloys and elimination of lattice translational symmetry.
领 域: [电子电信]