摘要
采用激光分子束外延方法在Al_2O_3(0001)单晶衬底上进行了Zn_(1-x)Cd_xO/Zn_O单量子阱结构的生长,通过控制基底温度、氧气分压等,获得了阱宽约为1.0,1.5和4.0 nm的单量子阱结构,研究了量子阱组分、表面形貌、荧光发射特性.结果表明,通过脉冲激光烧蚀陶瓷靶的方法获得的Zn_(1-x)Cd_xO中Cd含量x约为2%,外延膜表面平整均匀,界面质量良好,在325 nm He-Cd激光激发下,获得了非常强的光致荧光发射,1.0 nm量子阱结构荧光发射峰半高宽达到60 meV,通过量子阱宽度的调控,量子阱的发射峰从3.219 eV红移到3.158 eV,且随着阱宽的增加,量子限制效应变弱(阱宽4.0 nm样品),通过生长温度、气压条件的控制,量子阱的缺陷密度可控制在较低水平.
Zn1-xCdxO/ZnO single quantum well is grown by laser molecular beam epitaxy on Al2O3(0001) substrate.Single quantum well samples respectively with the well-widths of 1.0 nm,1.5 nm,4 nm are obtained by controlling the epitaxial temperature and oxygen pressure in the vacuum chamber.The chemical compositions,surface morphologies,crystal structures of the samples are carefully studied,and the results show that the Zn(0.98)Cd(0.02)O single quantum wells are of high quality with very smooth surface(with the root mean square value of 0.6 nm in 20 μm × 20μm area) and good crystal structure.Quite a strong photoluminescence emission is obtained at 3.158 3.219 eV from the ZnCdO single quantum well at 4 K under a 325 nm He-Cd laser by tuning quantum well-width.The full width of half maximum of the photoluminescence emission peak of the 1.0 nm quantum well reaches 60 meV,which indicates a strong quantum confinement effect.
出处
《物理学报》
SCIE
EI
CAS
CSCD
北大核心
2016年第5期310-314,共5页
Acta Physica Sinica
基金
中国工程物理研究院激光聚变研究中心等离子体物理重点实验室基金(批准号:9140C680501110C6803)
中南大学中央高校基本科研业务费专项基金(批准号:ZY2015681)资助的课题~~
关键词
ZnCdO量子阱
荧光光谱
激光分子束外延
量子限制效应
ZnCdO quantum well
photoluminescence
laser molecular beam epitaxy
quantum-confinement effect