根据EACVD系统的实际几何特点和工艺参数建立了该系统的三维流场有限元模型,研究了衬底温度及摆动周期、热丝参数、进气口参数对衬底表面流场均匀性的影响。结果表明:衬底低速摆动情况下摆动周期的变化对衬底表面流场的分布没有影响,衬底温度,热丝参数,进气口参数对衬底表面流场都有一定的影响,其中,热丝的排列方式以及进气口气体流量对衬底表面流场的影响最大。最后,采用一组优化的沉积参数进行金刚石膜衬底表面流场的仿真计算,结果表明:采用优化的沉积参数可以使衬底表面气体流速和流场的均匀性都得到很大提高,此研究结果为制备高质量金刚石膜提供理论依据。
Finite element model of three dimensional flow field of EACVD system was established based on its actual geometric characteristics and process parameters.The effect of the swing period,the substrate temperature,the filament parameters and the air inlet parameters on uniformity of flow field on the substrate surface were studied.The results show that the change of the swing period makes no difference to the distribution of flow field on the substrate surface while the substrate swings slowly.The substrate temperature,the filament parameters and the air inlet parameters influence flow field on the substrate surface to some extent.Among these factors,the filament array mode and the gas flux of the air inlet are of most influential.The simulation carried out by adopting a group of optimized deposition parameters shows that the uniform flow field can be obtained with optimized deposition parameters.The simulation results may offer theoretical foundation to the preparation of high quality diamonds.