Development of the Patch-Type Cutoff Sensor for Plasma Monitoring

Real-time and accurate measurement of electron density is necessary in current and next generation semiconductor and display plasma processes to improve wafer processing result and yield. For this, there have been a few studies on the microwave plasma diagnostic methods, such as the flat cutoff sensor [1]. However, most sensors have a coaxial structure or are several millimeters thick. In this study, we developed a Patch-Type Cutoff Sensor that enables microwave transmission and plasma measurement even if the coaxial structure is not maintained. We performed the optimization of the sensor structure using electromagnetic wave simulation, and verified it experimentally.