Online re-optimization as a powerful part of enhanced strategies in optical broadband monitoring

Abstract

Enhanced strategies in optical broadband monitoring allow for thin film deposition under rapid production conditions with very high process stability. Recent developments in the field include simulation techniques with virtual deposition systems, to enable a pre-selection of different multilayer designs, and hybrid process control strategies which combine optical monitoring with quartz crystal monitoring. In particular, automated online error re-calculation and design re-optimization are presently in the focus of research to improve the efficiency of deposition plants. In this contribution a developed re-optimization module is presented, and the resulting increase in production yield of complicated multilayer designs is demonstrated by deposition examples. Besides automated design changes directly initiated by the re-calculation software, the presented approach also considers supervising functions that stop the deposition run when critical errors are detected.