Fabrication and performance of a novel suspended RF spiral inductor

MEMS suspended inductors are susceptible to deformation under external forces, which can lead to the degradation of their electrical properties. The mechanical response of the inductor to a shock load is usually solved by a numerical method, such as the finite element method (FEM). In this paper, the transfer matrix method of linear multibody system (MSTMM) is used to solve the problem. The natural frequencies and mode shapes of the system are obtained first, then the dynamic response by modal superposition. The time and position of the maximum displacement response and the maximum Von Mises stress are determined theoretically and independently of the shock. Furthermore, the effects of shock amplitude and frequency on the response are discussed. These MSTMM results agree well with those determined using the FEM. We achieved an accurate analysis of the mechanical behaviors of the MEMS inductor under shock load.

Section: Introductionmentioning

confidence: 99%

Mechanical Response of MEMS Suspended Inductors under Shock Using the Transfer Matrix Method

Zheng

2023

“…However, due to the semiconductor characteristics of silicon, which is usually used as the substrate of the inductors, there are serious losses in the inductors on the traditional RFIC, which makes the quality factor (Q factor) of the inductors low [1][2][3]. Microelectromechanical systems (MEMS) suspended inductors fabricated by MEMS technology can greatly reduce the loss of inductor by lifting the coil several micrometers above the substrate [4][5][6][7][8], so as to achieve a higher Q and meet the requirements of high-performance RFIC for inductors. By optimizing the structure of the inductor, the radio frequency performance of the inductor including Q factor and inductance can be improved.…”

Section: Introductionmentioning

confidence: 99%

Analysis of the Failure and Performance Variation Mechanism of MEMS Suspended Inductors with Auxiliary Pillars under High-g Shock

2020

Microelectromechanical systems (MEMS) suspended inductors have excellent radio frequency (RF) performance and they are compatible with integrated circuit (IC). They will be shocked during manufacturing, transportation, and operation; in some applications, the shock amplitude can be as high as tens of thousands of gravitational acceleration (g, 9.8 m/s2). High-g shock will lead to the inductor deformation which affects its performance or even failure of the inductor structure. However, few studies have been carried out on the inductors under high-g shock. In this study, a kind of MEMS suspended inductor with excellent RF and mechanical performance is designed and fabricated. The failure and performance variation mechanism of the inductor under high-g shock is analyzed by measuring and comparing the performance measurement results and the π model parameters extraction results of the inductors before and after air cannon shock test. The results show that the increase of energy loss caused by substrate parasitic effect and the properties variation of the coil material affected by high-g shock are the main reasons for the decrease of RF performance parameters, and the critical stress exceeding the interlayer adhesion is the main reason for the failure of the inductor.

“…Inductors play an important role in radio frequency integrated circuits (RFICs) [1,2,3]. Compared with traditional complementary metal oxide semiconductor (CMOS) on-chip inductors, micro-electromechanical systems (MEMS) suspended planar spiral inductors have excellent radio-frequency because the inductor coils are lifted several micrometers above the substrate [4,5,6,7]. MEMS suspended inductors have benefits in improving the performance of RFICs.…”

Section: Introductionmentioning

confidence: 99%

Analysis of the Performance Variation Mechanism of MEMS Suspended Inductors under Mechanical Shock

2019

Micro-electromechanical system (MEMS) suspended inductors have been widely studied in recent decades because of their excellent radio frequency performance. However, the deformation of the inductor coil and the performance variation usually occur to the MEMS suspended inductors when the inductors are under mechanical shock. Few studies have been carried out on the performance variation of MEMS suspended inductors under shock. In this study, the mechanism of the performance variation of MEMS suspended inductors under mechanical shock is analyzed by combining theoretical analysis and experiments. A theoretical analysis based on the lumped-element equivalent model is presented and shock tests are carried out. The shock tests show that the main reason of the MEMS suspended inductor performance variation after mechanical shock is the variation of the substrate parasitic effect, which is caused by the variation of the suspension height of the inductor after shock. The test results agree with the theoretical analysis.