单个砷原子在砷化镓富砷表面的迁移行为.doc

文档介绍：
单个砷原子在砷化镓富砷表面的迁移行为#
李坤1,杨雯2,杜诗文2**
(1. 太原科技大学应用科学学院;
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2. 太原科技大学材料科学与工程学院)
摘要:采用剢子动力学方法计算了单个砷原子在砷化镓(001)β2(2×4)富砷表面迁移的势能
面,研究了砷原子在该表面上的迁移行为。结果表面,在该表面存在一部剢低能量的吸附位
和一条平行于砷二聚体的迁移路径。且在这条迁移路径中,砷原子迁移所需要跃过的势垒均
小于 。因此在常温情况下,砷原子有可能在这条迁移路径中聚合成团簇。
关键词:表面;原子迁移;分子动力学
中图分类号:O485; ;
Diffusion of an extra As atom on GaAs As-rich surface
LI Kun1, YANG Wen2, Du Shiwen2
(1. College of Applied Science, Taiyuan University of Science and Technology, Taiyuan 030024, P.
R. China;
2. College of Materials Science and Engineering, Taiyuan University of Science and Technology,
Taiyuan 030024, P. R. China)
Abstract: The potential energy surface for the migration of an extra As atom on the GaAs (001)
β2 (2 × 4) surface was mapped out to study the diffusing behavior of the As atom by performing
molecular dynamics calculations. Based on our calculations, some lower-energy sites and one
possible pathway paralleling to the As dimers were found for the adsorption and diffusion of an
extra As atom in this surface. According to the relative energies in the pathway, the energy barrier
for the diffusing of the As atom was less than . Therefore it was inferred that the As atoms
preferably kept their diffusion and formed clusters in the pathway at room temperatures.
Key words: Surface; Diffusion of an atom; Molecular dynamics
0 引言
砷化镓作为一种典型的I