Rose F, Fujita H, Kawakatsu H
Laboratory for Integrated Micro Mechatronic Systems/Centre National de la Recherche Scientifique (UMI 2820), Institute of Industrial Science, University of Tokyo, 4-6-1 Komaba, Meguro-ku, Tokyo 153-8505, Japan. Center for International Research on Micro Mechatronics, Institute of Industrial Science, University of Tokyo, 4-6-1 Komaba, Meguro-ku, Tokyo 153-8505, Japan.
Nanotechnology. 2008 Jan 23;19(3):035301. doi: 10.1088/0957-4484/19/03/035301. Epub 2007 Dec 11.
We report a phenomenological study of Ga dots and ripples created by a focused ion beam (FIB) on the GaAs(001) surface. Real-time observation of dot diffusion and ripple formation was made possible by recording FIB movies. In the case of FIB irradiation with a 40 nA current of Ga(+) ions accelerated under 40 kV with an incidence angle of θ = 30°, increasing ion dose gives rise to three different regimes. In Regime 1, dots with lateral sizes in the range 50-460 nm are formed. Dots diffuse under continuous sputtering. In Regime 2, dots self-assemble into Bradley and Harper (BH) type ripples with a pseudo-period of λ = 1150 ± 25 nm. In Regime 3, ripples are eroded and the surface topology evolves into microplanes. In the case of normal incidence, FIB sputtering leads only to the formation of dots, without surface rippling.
我们报告了一项关于聚焦离子束（FIB）在GaAs(001)表面产生的Ga点和波纹的现象学研究。通过记录FIB电影实现了对量子点扩散和波纹形成的实时观察。在用40 kV加速、入射角θ = 30°的40 nA电流的Ga(+)离子进行FIB辐照的情况下，增加离子剂量会产生三种不同的状态。在状态1中，形成横向尺寸在50 - 460 nm范围内的量子点。量子点在连续溅射下扩散。在状态2中，量子点自组装成具有伪周期λ = 1150 ± 25 nm的布拉德利和哈珀（BH）型波纹。在状态3中，波纹被侵蚀，表面拓扑结构演变成微平面。在垂直入射的情况下，FIB溅射仅导致量子点的形成，而不会产生表面波纹。
