A Bonded-Micro-Platform Technology for Modular Merging of RF MEMS and Transistor Circuits

A technology has been demonstrated that uses compression bonding to modularly combine platform-supported μmechanical filters with integrated BiCMOS transistor circuits while attempting to preserve the Q of mounted resonators. In this process, μmechanical devices are first fabricated onto SOI platforms, which are then released (together with devices) and compression bonded onto a transistor circuit wafer, making electrical connections at the bonds. Prior to bonding, while mounted on unreleased platforms, 6 MHz and 40 MHz clamped-clamped beam μmechanical resonators exhibit Q’s of 2,000 and 300, respectively. After release and bonding to the circuit wafer, the Q’s are degraded to 520 and 120, respectively. Poor bonding quality is identified as a likely reason for the observed Q reductions.