Silicon-based tunable optical thin-film filters

Inhalt:
A MEMS-based tunable optical filter is presented. The filter consists of two distributed Bragg reflectors (DBR) with a solid-state silicon cavity in between. Tuning is achieved by varying the cavity’s refractive index through thermal modulation. The fabricated of the optical filter is completely based on plasma enhanced chemical vapour deposition (PECVD). Microsystem technology is employed to miniaturize the device and improve its functionality. Such a filter is essential for monitoring and reconfiguration of optical data communication networks and is also applicable to gas sensing. Because of its excellent optical performance the filter is already suitable for monitoring optical communication systems.