Self-assembling MEMS variable and fixed RF inductors

Inductors play a key role in wireless front-end circuitry, yet are not gene rally well suited for conventional RF integrated-circuit (RFIC) fabrication processes. We have developed inductors that can be fabricated on a convent ional RFIC silicon substrate, which use warping members to assemble themsel ves away from the substrate to improve quality factor (Q) and self-resonanc e frequency (SRF), and to provide a degree of variation in inductance value . These self-assembling variable inductors are realized through foundry pro vided microelectromechanical systems (MEMS) processing and have demonstrate d temperature stable Q values greater than 13, SRF values well above 15 GHz , and inductance variations greater than 18%. Simulations suggest the poten tial for Q values above 20 and inductance variations greater than 30%, with optimized processing.