Abstract: A processor is provided for an improved semiconductor etching system which generates a series of multi-bit digital output code words. The processor provides an endpoint detector for determining if one of the digital output code word has reached a predetermined endpoint level and for generating a control signal to stop etching of a wafer. The processor further provides a standard endpoint curve corresponding to standard etching of a standard wafer. A normalizer is provided for normalizing the current endpoint curve generated from the series of multi-bit digital code words for a wafer being etched with respect to the standard endpoint curve and for providing a normalized current endpoint curve.

Abstract: An optimal gap is determined between a lower electrode and an upper electrode in a plasma processing device. A gap is set between the lower electrode and the upper electrode, and a substrate is processed in the plasma processing chamber. The processing results are obtained, and the processing rate and uniformity are determined from the processing results. The processing rate and uniformity are plotted with the gap setting. The steps of setting, processing, obtaining, determining, and plotting are repeated for additional substrates, the gap setting being different for each substrate. The optimal gap setting is selected as the gap setting corresponding to an optimal processing rate and an optimal uniformity.