For the presence of the suspended spiral coil, the MEMS suspended inductor has unsatisfactory mechanical performance, and use of the inductor in shock environments is restricted. Aimed at this problem, this paper designed an on-chip integrated MEMS suspended spiral inductor with a novel step-shaped spiral coil. A simple cantilever beam was used to explain the design principle, and the radio frequency performance was considered together with the mechanical performance in the design to ensure the high-Q characteristic, which is the main and inherent advantage of the MEMS suspended inductor. The fabrication process of the inductor is briefly introduced. ANSYS and HFSS were used to study the mechanical performance and the radio performance of the inductor, respectively. To compare with simulation results of the introduced inductor (denoted by ‘Inductor- A’), a conventional MEMS suspended inductor with an equal cross-section area spiral coil (denoted by ‘Indcutor-B’) and a conventional MEMS suspended inductor with an additional support pillar (denoted by ‘Inductor-C’) were also analyzed by using ANSYS and HFSS at the same time. The results show that the anti-overload capacity of Inductor-A was improved by about three times that of the Inductor-B, while radio frequency performances of both inductors were almost the same, and accordingly, the quality factor of Inductor-A was much higher than that of Inductor-C, while mechanical performances of both inductors were almost the same. The results indicate that the inductor presented in this paper has excellent radio frequency performance and mechanical performance.

micro electro mechanical system  /  suspended spiral inductor  /  step-shaped spiral coil