Design and Fabrication of High-Q Spiral Inductors Using MEMS Technology

This paper presents the design and modeling, fabrication and characterization of suspended spiral inductors on silicon substrate. The substrate materials underneath the inductor coil are removed by micromachining process to reduce the substrate loss which enables high frequency operation. A complete Library of spiral inductors with different line width, line spacing and number of turns have been designed and simulated. The results show that the Q factor as well as the self resonance frequency fsrf is greatly improved by removing the silicon underneath the inductor. The spiral inductors have a peak Q-factor of 35, and the maximum resonance frequency of the inductors is about 16 GHz. Fabrication of 2.5 turns inductor using MEMS technology is carried out. Measurements and characterization results are presented in this work. Key-Words: Spiral inductor, MEMS technology, High Q-factor, RF applications.