Evaluation of Ellipsometric Monitors for Process Control of High Temperature Superconductors

Current methods of manufacturing high temperature thin lm superconductors require increasingly more precise and accurate thin lm diagnostics to ensure high quality superconductors. There are several diagnostic tools for monitoring thin lms. However, due to the complex nature of superconducting thin lm stacks, ellipsometric methods are well suited for this application. This study investigates various ellipsometric methods in simulated process control environments.

A computer program was developed to generate ellipsometric data for given film stack characteristics and experimental geometry, and to analyze simulated ellipsometric data to recover optical parameters of the given film stack. The program was used to investigate the effects of systematic errors in the angle of incidence, one of the primary sources of systematic error in a process control environment. It is found that for the given expected film characteristics, the experimental geometry can be selected to minimize the effects of angle of incidence error.