Integration of Self-Assembled 3-D RF Passive Components with Thin-Film Microstrip Lines

A fabrication process has been developed which allows the combination of thin film microstrip transmission lines with released metal structures which can then be rotated out-of-plane by surface tension self-assembly. The transmission lines allow low-loss, impedance matched feeds to the lumped element components. The use of self-assembly allows decoupling from lossy substrates, which can greatly improve the Q and operating frequency range. This is demonstrated for inductors, where Q above 30 is achieved on low resistivity silicon, with no self resonance up to 12 GHz. The process technique avoids all substrate modification and high temperature steps.