MgZnO半导体材料光致发光以及共振拉曼光谱研究  

Study of MgZnO Semiconductor Materials Using Photoluminescence and Resonance Raman Spectroscopy

作　　者：王玉超[1] 吴天准[1] 张权林[1] 陈明明[1] 苏龙兴[1] 汤子康[1,2] 

机构地区：[1]中山大学理工学院光电材料国家重点实验室,广东广州510000 [2]香港科技大学物理系

出　　处：《发光学报》2013年第9期1149-1154,共6页Chinese Journal of Luminescence

基　　金：国家"973"计划(2011CB302000);国家自然科学基金委重点项目(51232009)资助项目

摘　　要：用分子束外延设备在c面蓝宝石衬底上生长得到高质量Mg x Zn1-x O薄膜。X射线衍射显示,当Mg摩尔分数在0~32.7%范围内时,薄膜保持六方结构,(002)衍射峰半高宽为0.08°~0.12°,薄膜结晶质量与现有报道的最高水平相当。随着薄膜中Mg含量的增加,紫外发光峰由378 nm蓝移至303 nm。对Mg0.108Zn0.892O薄膜变温光致发光光谱的研究发现,束缚激子发光随温度变化存在两个不同的猝灭过程。对不同Mg含量薄膜共振拉曼光谱的研究发现,A1(LO)声子模频移与Mg含量在一定范围内呈线性关系,这为确定Mg x Zn1-x O薄膜中的Mg含量提供了一种简单高效的方法。通过拉曼光谱与X射线衍射对比研究发现,拉曼光谱在确定MgZnO材料相变时具有更高的灵敏度。最后,研究了Mg0.057Zn0.943O薄膜的变温共振拉曼光谱,对A1(LO)和A1(2LO)声子模随温度而变化的现象给出了一定的理论解释。High-quality Mg x Zn 1-x O semiconductor materials had been grown using plasma-assisted molecular beam epitaxy(P-MBE) on c-plane sapphire substrate by inserting special metal buffer layers.X-ray diffraction results show that the MgZnO films keep hexagonal structure when the mole fraction of Mg varies from 0 to 32.7%,and the full width at half maximum(FWHM) of the films are 0.08° ~ 0.12°.To the best of our knowledge,the crystal quality should be one of the highest level ever reported.With the increasing of Mg content in the films,the room-temperature photoluminescence(PL) of ultraviolet emission peaks are shifted from 378 nm to 303 nm.A detailed study on Mg 0.108 Zn 0.892 O film by temperature-dependent photoluminescence shows that the bound exciton emitting has two different quenching processes with the temperature increasing.In addition,resonance Raman spectroscopy indicates that there is a linear relationship between the content of Mg in the films and the A 1(LO) phonon mode frequency shift.This relationship provides a simple and efficient method to determine Mg content in Mg x Zn 1-x O films.It is found that Raman spectroscopy is more sensitive to the component phase change than the X-ray diffraction characterization.Finally,the temperaturedependent Raman spectroscopy was employed for Mg 0.057 Zn 0.943 O and a theoretical explanation of A 1(LO) and A 1(2LO) phonon mode frequency shift with temperature was given and discussed.

关 键 词：MGXZN1-XO 分子束外延 X射线衍射 光致发光 共振拉曼光谱 

分 类 号：O482.31[理学—固体物理]