Probing ultra-thin amorphous carbon films by means of nanometric silver islands

Abstract The optical properties of silver island films in ultra-thin sandwich samples are investigated. The samples essentially represent a three-layer system, where an amorphous carbon layer is embedded between two amorphous silicon films. The carbon layer itself contains nanometric silver islands. Due to the spatially close carbon–silicon interface, a change in the carbon film thickness affects the resonance frequency of the surface plasmon excitation in the silver islands. In this way, the fraction of the optical loss that is caused by the silver islands may be shifted in the wavelength range between 900 and 570 nm.