Ti/Fe(001)体系异质外延生长初期外延岛尺寸作用机制探究  

Mechanism Probe for Effect of Epitaxial Island Size on Hetero-Epitaxial Initial-Growth in Ti/Fe(001) System

作　　者：黄河[1] 颜超[2] 赖新春[1] 刘天伟[1] 张庆瑜[2] 

机构地区：[1]表面物理与化学国家重点实验室,四川绵阳621900 [2]大连理工大学三束材料改性国家重点实验室,辽宁大连116024

出　　处：《原子能科学技术》2010年第4期408-413,共6页Atomic Energy Science and Technology

摘　　要：采用嵌入原子方法,运用分子动力学,研究了Ti/Fe(001)体系中异质外延初期生长随岛尺寸演变的规律。结果表明:Ti在Fe(001)表面外延生长时存在生长模式转变的临界尺寸,临界尺寸以上,外延岛边缘原子通过向上迁移运动来降低体系能量。体系的界面微观失配度和膜基结合能随外延岛的生长而降低,晶体结构的失配导致外延岛原子间的平均键长小于Fe基体原子间的平均键长。外延岛原子间平均键长的变化将引起外延岛和基体微观形态以及应力应变状态的改变。Molecular dynamics with embedded atom method was used for research regularity of hetero-epitaxial initial-growth evolving with island size in Ti/Fe（001） system. The results show that the epitaxial island critical size which determinates growth model exists in the process of Ti growing on Fe（001） surface, the atoms on the edge of island decrease system energy through upward transportation while epitaxiat island size is above the critical value. The interface mesoscopic mismatch and adhesion energy between epitaxial island and substrate decrease with the growth of epitaxial island and crystal structure mismatch lead the average bond of island to be less than that of Fe substrate. The variation of epitaxial island average bond will affect micro-morphology, stress and strain condition of epitaxial island and substrate.

关 键 词：嵌入原子方法 分子动力学 异质外延 

分 类 号：O562.4[理学—原子与分子物理]