GaInP薄膜KMC生长并行计算模拟与可视化研究

以金属有机化学气相沉积(MOCVD)技术在GaAs衬底上生长GaInP太阳电池薄膜材料为对象,将MOCVD反应室内气体热流场CFD数值模拟的结果作为生长参数,运用动力学蒙特卡罗(KMC)方法对GaInP薄膜生长过程进行了并行计算模拟,给出了数据分布方式和通信优化策略进行负载平衡并降低通信开销,实现了真实沉积条件下基于大规模粒子的薄膜生长仿真,解决了单机计算能力的不足,缩短了仿真计算时间。模拟结果与试验一致性较好,为优化MOCVD生长GaInP薄膜的工艺参数提供理论依据,对于使用MOCVD生长高质量薄膜材料的太阳电池具有现实意义。

基于KMC方法的Ag膜生长初期的计算机模拟

文中针对银的晶格特征和银薄膜的生长特性,建立了基于KMC(Kinetic Monte Carlo)方法的银薄膜生长模型,模拟了单层Ag膜生长初期的表面形貌。在周期性基底且层间原子间采用交错排列的方式条件下,采用EAM(Embedded Atom Method)计算原子间作用势,并针对金属Ag的晶格特征及其成膜特性进行建模,编程,实验。实验结果表明:在温度不变的情况下,随着覆盖度的增加,表面原子的数量增多,且出现二维岛状生长;岛的生长形貌经历了从分散到凝聚生长的过程;原子岛的数量减少,同时岛的尺寸在增大。

Atomic scale KMC simulation of {100} oriented CVD diamond film growth under low substrate temperature—Part I Simulation of CVD diamond film growth under Joe-Badgwell-Hauge model

The growth of (100} oriented CVD (Chemical Vapor Deposition) diamond film under Joe-Badgwell-Hauge (J-B-H) model is simulated at atomic scale by using revised KMC (Kinetic Monte Carlo) method. The results show that: (1) under Joe's model, the growth mechanism from single carbon species is suitable for the growth of (100) oriented CVD diamond film in low temperature; (2) the deposition rate and surface roughness (Rq) under Joe's model are influenced intensively by temperature (Ta) and not evident bymass fraction W of atom chlorine; (3)the surface roughness increases with the deposition rate, i.e. the film quality becomes worse with elevated temperature, in agreement with Grujicic's prediction; (4) the simulation results cannot make sure the role of single carbon insertion.

Atomic scale KMC simulation of {100} oriented CVD diamond film growth under low substrate temperature-Part Ⅱ Simulation of CVD diamond film growth in C-H system and in Cl-containing systems

The growth of {100}-oriented CVD diamond film under two modifications ofJ-B-H model at low substrate temperatures was simulated by using a revised KMC method at atomicscale. The results were compared both in Cl-containing systems and in C-H system as follows: (1)Substrate temperature can produce an important effect both on film deposition rate and on surfaceroughness; (2) Aomic Cl takes an active role for the growth of diamond film at low temperatures; (3){100}-oriented diamond film cannot deposit under single carbon insertion mechanism, which disagreeswith the predictions before; (4) The explanation of the exact role of atomic Cl is not provided inthe simulation results.

MOCVD的GaInP薄膜生长可视化研究

运用动力学蒙特卡罗(KMC)方法对金属有机化学气相沉积(MOCVD)生长GaInP薄膜过程进行了模拟;将模拟的结果与虚拟现实(VR)系统开发的软件开发包Open Inventor接口,实现了MOCVD反应室内GaInP薄膜生长过程的可视化仿真。模拟仿真结果准确直观地展示了MOCVD反应室内GaInP薄膜生长的过程,揭示了扩散时间和衬底温度对GaInP薄膜形貌的影响规律;可视化结果为优化MOCVD生长GaInP薄膜的工艺参数提供理论依据。

一种改进的CVD金刚石膜生长过程原子尺度三维仿真方法

蒙特卡洛动力学(Kinetic Monte Carlo-KMC)仿真方法通过结合金刚石膜生长表面的原子结构和形貌特性,以及对CVD金刚石膜生长过程在原子尺度上的三维表征,可以形象描述CVD金刚石薄膜原子尺度生长过程。本文在介绍KMC方法的同时,分析了所存在问题,并对原有KMC方法加以改进,使之更准确地反映CVD金刚石薄膜原子尺度的生长规律。