PECVD镀膜机等离子体静电探针诊断

Plasma Diagnosis with Langmuir Probe in Plasma Enhanced Chemical Vapor Deposition

开发了一个朗缪尔探针等离子体诊断系统,对PECVD真空镀膜机进行了等离子体参数诊断。该镀膜机内的等离子体是电容偶合激发方式的氩等离子体,激发源为射频电源(13.56MHz)。在射频功率为40W到140W的范围内,使用该朗缪尔探针对镀膜机中氩等离子体的参数(等离子体密度和电子温度)进行了诊断分析。结果表明:电子温度在2.7eV和6.4eV之间,并且随着射频功率的增加而降低。而等离子体的密度在0.85×1015m-3到8×1016m-3的范围随着射频电源的增加而增加。

Langmuir probe was designed and built to diangnose capacitive coupled plasma （CCP） in the film growth by RF plasma enhanced chemical deposition （PECVD）. The discussion focuses on design of the Langmuir probe. The impact of various argon plasma characteristics, includig the plasma density, electron temperature and plasma potential, on the film growth was studied to improve the quality of the coatings. The measured plasma density ranges from 8 × 10^16m^- 3to 0.85 × 10^15m^-3and increases with an increase RF power from 40W to 120W.The electron density varies from 2.7eV to 6.4eV, and decreases also with an increase of RF power. We suggest that a judicious choice of plasma characteristics may optimize the coating.