In液滴在GaAs(001)表面扩散行为的研究

Study on the diffusion behavior of In droplets on GaAs surface

量子点的物理与光电性质主要依赖于其尺寸及密度参数,而量子点的密度、高度等参数又控制着原子在衬底上的成核行为.本文采用液滴外延法在GaAs(001)表面生长金属In液滴,研究了In液滴的扩散运动与衬底温度和沉积速率之间的关系,研究发现,随着衬底温度的升高和沉积速率的降低,In液滴尺寸增大密度却降低.通过得到的实验数据,拟合关于In液滴密度与衬底温度和沉积速率的曲线,分析了量子环的生长机制,并根据原子的表面迁移行为,进一步分析其表面原子扩散机理.

The basic physical properties and applications of semiconductor quantum dots have attracted the attention of researchers.The properties of quantum dots mainly depend on the size and density,and the density,height and other parameters of quantum dots control the nucleation of adatoms on the substrate.In this paper,metal In droplets are grown on GaAs(001)surface by droplet epitaxy.The relationships of the diffusion movement of In droplets with substrate temperature and deposition rate are studied.It is found that with the increase of substrate temperature and the decrease of deposition rate,the size of in droplets increases,but the density decreases.Through the experimental data obtained,the curves of In droplet density with substrate temperature and deposition rate are fitted,the growth mechanism of quantum ring is analyzed,and the mechanism of surface atomic diffusion is further analyzed.