氧化硅缓冲层对于退火形成锗量子点的作用研究

摘要

Ge is deposited on an ultrathin SiO~ layer obtained chemically at room temperature, followed by annealing process. High density and uniform Ge quantum dots, rather than superdomes in traditional treatment, are obtained. Growth mechanism is suggested to explain the unusual microstructure dependence on annealing temperature. Raman spectrum is used to investigate the strain. Two peaks are found to be around 500 nm and 1350 nm respectively from the photoluminescence characterization.%在化学氧化得到的二氧化硅薄层覆盖的硅衬底上，室温淀积锗膜并进行后期退火处理．实验表明，不同于传统退火过程形成大岛，通过一定工艺的控制可以获得高密度（～10^11 cm^-2）的均匀锗量子点．研究了后期退火温度对量子点的结构影响的局部反常规律并进行了原因分析．利用拉曼和荧光光谱研究了其应力和发光特性，发现在可见（500nm）和近红外（1350nm）的两个光致荧光峰出现．