凸曲率衬底外延生长界面演化的晶体相场模拟

【目的】采用晶体相场模型模拟衬底分别为平面和凸面时外延层的生长过程。【方法】研究晶格错配度较大(ε=0.10)且衬底倾角较小(2~5°)时,系统自由能和外延层总原子数的变化,分析衬底曲率和衬底倾角对系统自由能曲线和总原子数曲线的影响。【结果】研究表明:衬底曲率为平面时,系统自由能随着倾角的增加而增加,外延层总原子数也随着倾角的增加而增加;衬底曲率为凸面时,系统自由能随着倾角的增加而减少,外延层总原子数也随着倾角的增加而减少。【结论】通过微调衬底的倾角能改变系统的自由能和外延层总原子数。

Simulation of Epitaxial Growth Interface on Convex Substrate Using Phase Field Crystal Method

Objective]Phase-field crystal model is employed to simulate the process of growth of epitaxial layer on plane and convex substrates.Methods]Under the condition of the large lat-tice mismatch （ε=0.10）and the small inclination,the influence of the curvature and the angle of the substrate on the systematic free energy and the total atomic number of the epitaxial layer were analyzed.Results]The results show that when the curvature of the substrate is plane,the free energy increase with the increase of the substrate angle,and so is the total atomic number of the epitaxial layer;when the curvature of the substrate is convex,the free energy decrease with the increase of substrate angle,and so is the total atomic number of the epitaxial layer.Conclusion]We can trimming the substrate angle to alter the system＇s free energy and the total atomic number of the epitaxial layer.