Evaluation of an in-situ particle monitoring system on an MxP plasma etch tool

Etching is the process where a layer is removed from a wafer surface through openings in a photoresist pattern. To monitor this process, a surface scan was employed. An in-situ particle monitor (ISPM) was installed on a plasma etch tool. The ISPM was incorporated so engineers and technicians could gain real-time information and notification of what is happening inside this tool during processing. Since ISPMs are real-time, they can catch problems as they are occurring. The ISPM detected two major problems on the plasma etch tool within a 3-wk period. The wafer scan data were monitored during this same time frame.