A monitoring and diagnostics system for a plasma etching cell

A three-level process monitoring and diagnostics system has been developed for a plasma etching cell. The physical and logical layout of this system is designed to co-exist with a proposed hierarchical cell control system. The cell control system design incorporates generic cell controller concepts and some of the SEMI Generic Equipment Model (GEM) specifications. At the lowest level of the system, equipment and process parameter monitoring is achieved. An AT-compatible computer serves as an information collection/router agent as well as an interpreter (gateway) between the SECS/RS-232 formatted messages received from the equipment controller system and the higher-level expert systems commands. At the top of the hierarchy, an expert systems package that resides on a SUN SPARC station and operates on an X-Windows environment collects information on the equipment and process from the AT compatible. The many system capabilities that result include: (1) pseudo real-time equipment and process monitoring, (2) equipment diagnostics and alarm reporting, (3) alarm logging; and (4) real-time equipment control