氧化硅衬底上高密度锗量子点的微结构研究  

Growth and Microstructures of High Density Ge Quantum Dots on SiO_2 Layers

作　　者：张磊[1] 叶辉[1] 皇甫幼睿[1] 詹文博[1] 刘旭[1] 

机构地区：[1]浙江大学现代光学仪器国家重点实验室,杭州310027

出　　处：《真空科学与技术学报》2011年第6期760-764,共5页Chinese Journal of Vacuum Science and Technology

摘　　要：以化学氧化生成的SiO2缓冲层作为衬底,利用分子束外延(MBE)系统通过直接生长以及后期退火的方式获得了高密度(1011cm-2)的锗量子点结构。借助于扫描电镜和电子衍射等进一步研究了其生长机理,与传统的S-K生长模式进行比较并给出了清晰的微观结构示意图。拉曼光谱证实此类微结构中有压应力的存在,而退火后的量子点则应力得到释放。The high density germanium quantum dots（QDs） were deposited by vacuum evaporation in a molecular beam epitaxy（MBE） reactor,on the Si substrates covered with ultra thin SiO2buffer layers.The impacts of the growth conditions on microstructures and properties of the Ge QDs were studied with scanning electron microscopy,energy dispersive spectroscopy,reflection high energy electron diffraction,and Raman spectroscopy.The results show that the Ge quantum-dots with a density of 1011 cm-2 were fabricated,and that the annealing relaxed the residue strains in the quantum-dots.The growth mechanisms and advantages over Stranski Krastanow（S-K） technique were also tentatively discussed.

关 键 词：锗岛 纳米微结构 分子束外延 二氧化硅 成核 

分 类 号：TN304.1[电子电信—物理电子学] TN304.05