化学气相淀积中甲烷含量变化的等离子体参数诊断

DIAGNOSIS OF PLASMA CHARACTERISTICS WITH THE VARIATION OF CH_4 CONCENTRATION IN CHEMICAL VAPOR DEPOSITION

一、引言 金刚石薄膜以其优异的特性越来越受到人们的重视。人们已用各种方法制备出金刚石薄膜、并详细研究了膜质量、膜的形貌与各种宏观参量的关系。在这里,含碳物源相对于氢气的浓度比对金刚石膜的结构和形貌的影响是相当严重的。从许多报道中可知。

During the diamond film deposition, the concentration ratio of hydrocarbon to hydrogen has strong influence on the structural and morphological features of diamond.In this study,the correlation between the concentration of CH4 and the plasma parameter was measured using single langmuir probe and microwave interferometer.The results show that at first the electron density increases with the concentration, then decreases after a concentration of about 2.5%.This is related to the experimental result that films produced at low CH4 concentration consist of distinct crystalline form and those at high concentration consist of globular aggregates of the diamond crystalline.