In this paper, the design of a resonant cavity enhanced photodetector, working at 1.55 µm and based on silicon technology, is reported. The photon absorption is due to the internal photoemission effect over the Schottky barrier at the metal–silicon interface. The photodetector is composed of a silicon layer in between multiple layers of Si–SiO 2, as a bottom mirror, and a thin Au film and dielectric coating, as a top mirror.