用MOCVD方法制备的GaN_(1-x)P_x三元合金的喇曼与红外光谱

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P掺入造成的局部晶格无序激活的振动模

Raman and Infrared Spectra Study of GaN1-xPx Ternary Alloys Grown by MOCVD

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.