小靶大基片镀膜的膜厚均匀性分析  

Film Thickness Uniformity of a Small-target Large-substrate Coating

作　　者：陈海峰[1] 薛莹洁 

机构地区：[1]陕西科技大学机电工程学院,西安710021

出　　处：《表面技术》2017年第2期108-112,共5页Surface Technology

摘　　要：目的通过改变传统基片与靶材的相对运动方式,来实现小靶材在大面积基片上的均匀镀膜。方法采用基片绕中心轴做匀速旋转运动,靶材沿着基片半径做直线间歇运动,并建立了相应的理论模型,通过数值分析软件MATLAB对膜厚进行分析拟合,研究靶基距、偏心距、靶材运动方式对膜层均匀度的影响。结果在靶基距H=30 mm时,膜厚均匀性主要受到两个重要参数的影响:靶材在各径向运动等距点的停顿时间T和移动步长d。与靶材在各径向运动等距点的停顿时间T=C(C为常数)的情况相比,当靶材的停顿时间T与其在基片上的覆盖面积A成正比增加时,膜厚的均匀性得到极大的改善。同时,膜厚的均匀性很大程度上取决于靶材的移动步长,膜层之间的差异性随着移动步长的减小而减小,结果显示当移动步长d=5mm时的膜厚均匀性最佳。改善基片中心附近的膜厚分布可以通过增加靶基距来实现,结果显示在偏心距e=0 mm、靶基距H≥70 mm时,膜厚相对偏差δ均小于0.1。结论该方法改变了传统靶材固定不动的方式,在薄膜沉积过程中,通过调节靶材的移动步长和停顿时间,能有效减小膜层之间的差异,从而获得均匀度较高的薄膜,对实际生产具有指导意义。The work aims to produce more uniform film in large substrate deposited with a small target by changing the relative motion between target and traditional substrate. With the substrate rotated at a constant speed around the center shaft, the target performed rectilinear intermittent motion along the substrate radius and relevant theoretical model was set up, then numerical analysis software MATLAB was used to analyze and fit film thickness and study the effects of target-to-substrate distance, eccentric distance and target motion mode on film uniformity. When the target-to-substrate distance H=30 ram, the film thickness uniformity was affected by two important parameters： target dwell time T and moving step size d of the target at each equidistant point of radial motion. Compared with the target dwell time T=C （C is a constant）, the film thickness uniformity increased significantly when target dwell time T changed in direct proportion to the target cover area on the rotating substrate. Meanwhile, the film thickness uniformity depended on moving step size of the target, the deviation between each film gradually reduced as the target moving step decreased, the results showed that the film uniformity was the best when the target moving step size d was 5 ram. The distribution of film thickness near the center of substrate could be improved by increasing the target-to-substrate distance, the relative deviation of film thickness δ was less than 0.1 with eccentric distance e=0 mm and target-to-substrate distance H≥ 70. By changing the traditional coating process with a stationary target and a rotary substrate, this new method is applicable to large substrate coating, which can realize higher uniformity and fewer differences between each layer of the film by adjusting moving step size and dwell time of the target during the process of film deposition. All the conclusions are of guiding significance to actual industrial production.

关 键 词：磁控溅射 沉积速率 理论模型 膜厚均匀性 停顿时间 移动步长 

分 类 号：TG174.442[金属学及工艺—金属表面处理]