Hassani Khosrow, Ashrafganjoie Mehdi, Tavassoly Mohammad Taghi
Appl Opt. 2016 Mar 1;55(7):1803-7. doi: 10.1364/AO.55.001803.
In this work we present the theoretical background and experimental procedure to measure the thickness of thin films by analyzing Fresnel diffraction patterns obtained from polychromatic illumination of phase-step samples. As examples of this technique, we measured the thicknesses of thin aluminum layers on glass substrates using three different broad-spectrum light sources. The results are in excellent agreement with independent interferometric measurements within less than 5% relative uncertainties.
