Intelligent control and diagnosis of chemical etch processes

Ckmical etching is sensitive to a number of process variables which need to be maintained in a certain relationship to achieve good quality product. We describe M intelligent control system to support chemical etch processes. The system serves siinultaneously two purposes: first it dispenses on-line expert advice on how to control chemical etching and, secondly, it constitutes a repository of qualitative knowledge and thus serves to codify the folklore of &aline etch control. Ttrp expert system has been prototyped using PROLOG and installed on the factory fkar.