直流磁控溅射膜厚分布实测与数值模拟研究

基于直流磁控溅射的基本原理,通过对小圆形磁控溅射平面靶的特点分析,建立了磁控溅射系统的几何模型,推导出了膜厚分布的数学理论模型。借助MATLAB数学软件,计算了不同靶基距下膜厚分布的理论数据,分析了靶基距变化时膜厚分布的特点。实测了两种不同靶基距下膜厚的分布,通过与理论数据的对比,验证了模型的可靠性。理论模型与实测数据的分析表明:随着靶基距的逐渐增大,膜厚的变化率减缓,膜层的平均厚度降低,膜厚分布的均匀性提高;在靶基距一定的情况下,增宽靶材的刻蚀区域会提高膜层厚度及其均匀性;基板上的膜厚分布大致呈现从中心到边缘逐渐变薄的趋势,膜层最厚的位置随着靶基距的增大,从靶材刻蚀最深处在基板上的投影位置,逐渐向基板中心转移。

Experimental and Numerical Study on Film Thickness Distribution of DC Magnetron Sputtering

Based on the analysis of the working principle of the small circular magnetron sputtering plane target, a mathematical theoretical model of film thickness distribution was established. With the software of MATLAB,the distribution of film thickness at different target base distances was calculated and analyzed, then the reliability of the model was verified by measuring the film thickness distribution under two different target base distances. The model and experimental results showed that as the target base distance increased, the change rate of the film thickness slowed down, the average thickness of the film layer decreased, and the uniformity of the distribution was improved. Furthermore, it also illustrated that at a certain target base distance, with widening the etching area of the target material, the thickness of the film and its uniformity would be increased. Finally, it put forward that the film thickness distribution on the substrate tended to be thinner from the center to the edge. With the increase of the target base distance, the thickest position of the film was gradually shifted to the center of the substrate from the projection position of the deepest part of the target etched groove on the substrate.