甚高频等离子体增强化学气相沉积大面积平行板电极间真空电势差分布研究

Study of space voltage distribution between large-area parallel-plate electrodes for very high frequency plasma enhanced chemical vapor deposition

采用二维准平面电路模型研究了甚高频等离子体增强化学气相沉积(VHF-PECVD)大面积平行板电极间真空电势差分布.计算结果表明:随平行板电极尺寸增加和激发频率提高,电势驻波效应成为影响电极间电势差非均匀分布的重要因素.在尺寸为1.2m×0.8m的大面积平行板电极上应用40.68和60MHz两种激发频率,通过功率馈入点数量和位置优化,计算获得非均匀性分别为±2.5%和±5.5%的真空电势差分布.这些数值计算结果为大面积平行板电极在VHF-PECVD中应用提供了重要的理论指导.

The two-dimensional quasi-planar circuit model is used to study the space voltage distribution between large-area parallel-plate electrodes of very high frequency plasma enhanced chemical vapor deposition（VHF-PECVD） reactor.The results show that the voltage standing wave effects become the important factor affecting non-uniform voltage distribution when the electrode dimensions and excitation frequency are increased.For a large-area parallel-plate electrode with 1.2 m by 0.8 m lateral dimension,driven respectively at frequencies of 40.68 and 60？MHz,the space voltage non-uniformity about ±2.5% and ±5.5% are obtained by optimization of the number and position of the power feeding points.These results provide important theoretical guidance for large-area parallel-plate electrodes used for VHF-PECVD.