Detecting Arcing Events in Semiconductor Manufacturing Equipment

Bi-polar arcs require a high voltage difference between two closely spaced points. As an example, if there is excessive deposition or contamination on the deposition and or cover ring in a physical vapor deposition tool (PVD) tool, a DC bipolar arc can occur leading to ablation of underlying materials, wafer breakage, or chamber damage caused by the discharge. In some cases these incidents are not identified until numerous wafers have been processed. Therefore, it is essential to identify arcing at the time of the event. In this paper, we address arc detection in a PVD chamber. The electrostatic chuck (ESC) critical parameter(s) are captured with 1000 Hz sampling frequency and signal processing techniques such as FFT and wavelet transforms are used to improve the signal-to-noise ratio enhancing the ability to isolate arcs from raw data. This methodology can be implemented on other plasma chamber types.