A novel technique for in situ measurements of thin film properties

Abstract

Abstract It is possible to measure the thickness dependence of resistivity during deposition on a moving substrate in all commercial sputtering systems by means of a small four-point probe resistance measurement arrangement (diameter, 100 mm; height, 5–10 mm) equipped with telemetric data transfer. Since the film properties are uniquely characterized by the thickness dependence of resistivity, for a high production yield of, for example, TaSi films the resistance—thickness relationship of a film whose properties fulfil all specifications must be reproduced by dynamic control of the deposition parameters. The influence of the plasma on the resistance measurements can be determined by using at least two different testing currents. The real film resistance and the current injected into the growing film can be calculated from the two values of resistance obtained. The injected current depends on the target power. It now appears to be possible to control the growth rate, the film thickness and the composition of metallic alloy films during deposition (co-sputtering).