A new and simple concept of tunable two-chip microcavities for filter applications in WDM systems

A new and simple two-chip concept for microcavities with application in den se wavelength-division-multiplexed systems as tunable optical filters is pr esented. The Fabry-Perot cavity is created without any costly distance hold er or sacrificial layer by simply utilizing the stress of the dielectric Br agg-mirrors against the semiconductor substrate. Electrostatic tunability i s achieved by making use of the high capacitance of the metallized cantilev ers holding the actuable membrane.