Goos-Hänchen shift: An optical phenomenon to measure thin film thickness of SiO2

Abstract

Thin films have found a niche in industry, technology and academic research. They are in semiconductors, display panels and wearable electronics. Here, we present a method for measuring the thickness of thin films by exploiting the Goos-Hanchen shift - an optical phenomenon that is a correction to the law of reflection. We calculated the GH shift for an air-SiO2-Si thin film to demonstrate the technique. We showed that we can distinguish thickness in the order of 1 nm to 10 nm. This technique is a simple, all optical, non-destructive method to measure thin film thickness.