摘要： A key to successfully have a consistent plasma processing is the maintaining a consistent process chamber condition over a certain production period. To alleviate the concern, in-situ process monitoring sensors are optical emission spectroscopy (OES), optical plasma monitoring sensor (OPMS), VI-probe, and self-plasma optical emission spectroscopy (SP-OES). During the deposition, we perform the monitoring of plasma condition associated with the applied RF power via OES, OPMS and VI-probe. In the chamber cleaning step using remote plasma system does not allow plasma monitoring through sidewall because the plasma is not formed in the process chamber, thus we employed SP-OES to monitor by-product gas chemistry during the chamber cleaning process step. Successful monitoring results with some useful applications, such as arc detection, part failure detection, and cleaning process chemistry analysis, are presented in this paper. The use of in-situ sensors with proper combination can help understanding plasma process better to achieve more precise control of the plasma processing.