Combination of MEMS processing and electroless copper plating for a novel RF inductor

A high-performance RF MEMS inductor is fabricated using an improved silicon-glass anodic-bonding and deep etching releasing process combined with electroless copper plating technology, both of which are our new development. The silicon spiral structure of the inductor is suspended over a high-resistance glass substrate with a large gap to the substrate. The silicon spiral structure is encapsulated completely by a plated copper film with good quality by taking advantage of the electroless copper plating technology. The best value of the inductor's quality factor has reached 27 at the frequency of 9 GHz tested with a network analyzer.