Automatic Control of Large-Scale Integrated Circuit Fabrication Processes-Process Control Algorithms

An automated manufacturing process control technique which reliably and repeatedly signals the end of integrated circuit fabrication is designed to make optimum use of either a process control operator who will inspect an on-line strip chart recording of process generated reflectance data and determine the optimum time to quench the fabrication process, or a small data processing system to signal the process end point. Results of automatically signaling the end of the process, via software implemented control algorithms for thin-film develop or etch processes, are presented.