Scattering transmission field of a photonic crystal surface wave to determine the thickness distribution of thin films

摘要: In present work, we use an electromagnetic surface mode excited at the interface of a finite one-dimensional photonic crystal utilizing a modified attenuated total reflection setup by capturing the images formed by the scattered surface waves under transmission to determine the thickness distribution of a non-uniform thin film (<100  nm) over an extended millimeter-sized area. The sensitivity of the proposed technique is analyzed by considering a step coating that presents two different regions of different thickness, which shifts the resonant conditions of the surface mode.