针对微机电系统(MEMS)悬浮电感机械性能较差问题,设计了一种应用于高过载环境的片上集成MEMS 悬浮螺旋电感。通过采用一种新颖的阶梯式螺旋线圈结构,有效减小了悬浮线圈在高过载环境中的变形与应力。利用ANSYS 和HFSS 软件对设计的电感力学性能和射频性能进行联合仿真。仿真结果表明,采用阶梯式螺旋线圈的MEMS 悬浮电感的抗过载能力比采用等截面线圈的传统MEMS 悬浮电感提高了近3 倍,并且具有相当的射频性能;与增加了支撑柱的等截面MEMS 悬浮电感相比,所设计的MEMS 悬浮电感具有与之相当的力学性能,但是其射频性能明显优于增加了支撑柱的电感。
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.
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