利用Monte Carlo方法对真空蒸发系统下的有机薄膜生长过程进行了模拟。在该系统模型中,Ns个点蒸发源均匀分布在半径为R的圆周上,基板相对蒸发源所在平面距离为d。利用该模型分析了膜厚分布以及点蒸发源个数Ns、蒸发源与基板的相对位置R和d对薄膜厚度均匀性的影响,并通过实验对仿真结果进行了验证。结果显示,增加蒸发源个数、增大相对基板位置均可以有效提高薄膜的均匀性,测试发现薄膜样品的精度Max-Min均保持在5%左右。
Based on the Monte Carlo method, a model of thermal evaporation system was proposed to simulate the growth process of organic thin-film. In this model, several point type sources were uniformly distributed around a circle and evaporated simultaneously. The effect of the number of point type sources, circle radius and source-substrate distance on the uniformity was analyzed. The results show that increasing the number of point type source, circle radius and source-substrate distance can effectively improve thin-film uniformity. Based on the method proposed in this study, the uniformity of the thickness in the organic layer was successfully controlled around 5%.