Uncertainty Considerations for Nonlinear Dynamics of a Class of MEMS Switches Undergoing Tip Contact Bouncing

Batch fabrication processes used to produce micro-electro-mechanical systems (MEMS) are prone to uncertainties in the system geometrical and contact parameters as well as material properties. However, since the common design method for these systems is typically based on precise deterministic assumptions, it is necessary to get more insight into their variations. To this end, understanding the influences of uncertainties accompanied by these processes on the system performance and reliability is warranted. The present paper focuses on predictions of uncertainty measures for MEMS switches based on the transient dynamic response, in particular, the bouncing behavior. To understand and quantify the influence of pertinent parameters on the bouncing effects, suitable mathematical model that captures the bouncing dynamics as well as the forces that are dominant at this micron scale are employed. Measure of performance in terms of second-order statistics is performed, particularly for the beam as well as beam tip parameters since excessive tip bounce is known to degrade switch performance. Thus, the present study focusses on the influence of uncertainties in the beam tip geometry parameters such as beam tip length/width as well as contact asperity variables such as the area asperity density and the radius of asperities. In addition to beam tip parameters, this study quantifies the effects of uncertainties in Young's modulus, beam thickness as well as actuation voltage. These influences on significant switch performance parameters such as initial contact time and maximum bounce height have been quantified in the presence of interactive system nonlinearities.

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Laterally Movable Triple Electrodes Actuator toward Low Voltage and Fast Response RF-MEMS Switches

Sensors ◽

10.3390/s19040864 ◽

2019 ◽

Vol 19 (4) ◽

pp. 864 ◽

Cited By ~ 1

Author(s):

Yasuyuki Naito ◽

Kunihiko Nakamura ◽

Keisuke Uenishi

Keyword(s):

Rf Mems ◽

Low Voltage ◽

Low Cost ◽

Actuation Voltage ◽

Fast Response ◽

Point Of View ◽

Micro Electro Mechanical Systems ◽

Mems Switches ◽

Rf Mems Switches ◽

Series Switch

A novel actuator toward a low voltage actuation and fast response in RF-MEMS (radio frequency micro-electro-mechanical systems) switches is reported in this paper. The switch is comprised of laterally movable triple electrodes, which are bistable by electrostatic forces applied for not only the on-state, but also the off-state. The bistable triple electrodes enable the implementation of capacitive series and shunt type switches on a single switch, which leads to high isolation in spite of the small gap between the electrodes on the series switch. These features of the actuator are effective for a low voltage and fast response actuation in both the on- and off-state. The structure was designed in RF from a mechanical point of view. The laterally movable electrodes were achieved using a simple, low-cost two-mask process with 2.0 µm thick sputtered aluminum. The characteristics of switching response time and actuation voltage were 5.0 µs and 9.0 V, respectively.

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Bouncing dynamics of electrostatically actuated NEM switches

Nano Express ◽

10.1088/2632-959x/ac4668 ◽

2021 ◽

Author(s):

Mohamed Bognash ◽

Samuel F Asokanthan

Keyword(s):

Contact Time ◽

Surface Effects ◽

Intermolecular Forces ◽

Operating Conditions ◽

Contact Dynamics ◽

Interactive System ◽

Initial Contact ◽

Performance Parameters ◽

Electrostatically Actuated ◽

Switch Performance

Abstract The aim of the present research is to understand the bouncing dynamic behavior of nano electromechanical (NEM) switches in order to improve the switch performance and reliability. It is well known that bouncing can dramatically degrade the switch performance and life; hence, in the present study, the bouncing dynamics of a cantilever-based NEM switch has been studied in detail. To this end, the repulsive van der Waals force is incorporated into a nano-switch model to capture the contact dynamics. Intermolecular forces, surface effects, and gas rarefication effects were also included in the proposed model. The Euler-Bernoulli beam theory and an approximate approach based on Galerkin’s method have been employed to predict transient dynamic responses. In the present study, performance parameters such as initial contact time, permanent contact time, major bounce height, and the number of bounces, were quantified in the presence of interactive system nonlinearities. The performance parameters were used to investigate the influence of surface effects and rarefication effects on the performance of an electrostatically actuated switch. Recommended operating conditions are suggested to avoid excessive bouncing for these types of NEM switches.

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Uncertainty Quantification for Cantilever Based MEMS Switches Considering Bouncing Dynamics

Volume 4A: Dynamics, Vibration, and Control ◽

10.1115/imece2016-67083 ◽

2016 ◽

Cited By ~ 2

Author(s):

Mohamed Bognash ◽

Samuel Asokanthan

Keyword(s):

Uncertainty Quantification ◽

Actuation Voltage ◽

Beam Width ◽

Operating Conditions ◽

Structural Elements ◽

Mems Switches ◽

Second Order Statistics ◽

Mems Fabrication ◽

Beam Thickness ◽

Switch Performance

Design methods of MEMS switches are typically based on deterministic approaches, where the parameters such as geometrical and physical properties as well as the operating conditions that characterize the behavior of systems are assumed to be known precisely. However, in practice, due to the batch-production processes used in MEMS fabrication as well as the micron-scale dimensions of the structural elements, consideration of uncertainties in system parameters and an understanding of their effects are warranted and should be investigated in order to improve the switch performance and reliability. The primary purpose of the present paper is to perform uncertainty quantification predictions for MEMS switches based on the transient dynamic response, in particular, the bouncing behavior. A suitable mathematical model that captures the bouncing dynamics and previously validated via experiments is employed for this purpose. In particular, quantification of performance in terms of second order statistics is performed to predict propagation of uncertainties in Young’s modulus, beam width, beam thickness as well as actuation voltage. The influence of these uncertainties on significant switch performance parameters such as initial bounce time as well as maximum bounce height have been quantified.

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The Influence of Ambient Pressure on the Dynamic Response of RF MEMS Switches

Volume 10: Micro and Nano Systems ◽

10.1115/imece2010-38575 ◽

2010 ◽

Author(s):

Avihay Ohana ◽

Oren Aharon ◽

Ronen Maimon ◽

Boris Nepomnyashchy ◽

Lior Kogut

Keyword(s):

Rf Mems ◽

Ambient Pressure ◽

Actuation Voltage ◽

Operating Conditions ◽

Experimental Results ◽

Release Time ◽

Q Factor ◽

Optimal Operating ◽

Mems Switches ◽

Rf Mems Switches

A study of the dynamic behavior of an RF MEMS switch is presented at different operating conditions. Experimental results for the actuation and release time and Q-factor as a function of the ambient pressure and actuation voltage are compared to theoretical predictions based on existing model. Optimal operating conditions (ambient pressure and actuation voltage) are determined based on two criterions: minimal actuation and release time and minimal oscillations upon switch release. In light of the experimental results optimal operating conditions determined to be 1.4Vpi at a pressure of a few torrs where actuation and release time are equal and short enough with no release oscillations. Three pressure regimes are identified with characteristic behavior of the Q-factor and actuation and release time in each regime. These behaviors have significant implications in many MEMS devices, especially RF MEMS switches.

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Design of Electrostatic Micro Mirrors for Improved Stability Though Surface Contact

Volume 1A: 25th Biennial Mechanisms Conference ◽

10.1115/detc98/mech-5839 ◽

1998 ◽

Author(s):

Timothy Moulton ◽

G. K. Ananthasuresh

Keyword(s):

Design Method ◽

Electrostatic Force ◽

Electrostatic Actuation ◽

Mems Devices ◽

Complex Dynamic ◽

Micro Electro Mechanical Systems ◽

Electrostatically Actuated ◽

Surface Contact ◽

Improved Stability ◽

Mems Process

Abstract There exists a need to stabilize the electrostatic actuation commonly used in Micro-Electro-Mechanical Systems (MEMS). Most electrostatically actuated MEMS devices act as variable capacitors with varying gap between the charged conductors. Electrostatic force in these devices is a nonlinear attractive force between the conductors resulting in a complex dynamic system. These systems are stable for only a small portion of the initial gap. In this paper a design method is presented for electrostatic micro-mirrors with improved stability. Controllable, stable electrostatic actuation can be achieved through surface contact between the two conductors. Once in contact with the surface, the compliance of the structure is used to stabilize the electrostatic actuation over a long range of motion. Beam based variable angle mirrors were designed and fabricated using the Multi-User MEMS Process at MCNC technology center. The design methods for stable electrostatic actuation were tested on these mirrors. Some characteristics are noted and their implementation into future designs is discussed.

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Scope of RF MEMS Technology for Microwave Circuits and Systems

Advances in Wireless Technologies and Telecommunication - Emerging Materials and Advanced Designs for Wearable Antennas ◽

10.4018/978-1-7998-7611-3.ch001 ◽

2021 ◽

pp. 1-22

Author(s):

Kanthamani Sundharajan

Keyword(s):

Rf Mems ◽

Low Cost ◽

Microwave Circuits ◽

Micro Electro Mechanical Systems ◽

Mems Switches ◽

Phased Array Antennas ◽

Array Antennas ◽

Rf Mems Switches ◽

Mems Technology ◽

Key Issues

Micro-electro mechanical systems (MEMS) technology has facilitated the need for innovative approaches in the design and development of miniaturized, effective, low-cost radio frequency (RF) microwave circuits and systems. This technology is expected to have significant role in today's 5G applications for the development of reconfigurable architectures. This chapter presents an overview of the evolution of MEMS-based subsystems and devices, especially switches and phased array antennas. This chapter also discusses the key issues in design and analysis of RF MEMS-based devices, particularly with primary emphasis on RF MEMS switches and antennas.

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Automated and Optimal Actuation Voltage Waveform Design for Contact Bouncing Mitigation of MEMS Switches

Key Engineering Materials ◽

10.4028/www.scientific.net/kem.609-610.1248 ◽

2014 ◽

Vol 609-610 ◽

pp. 1248-1253

Author(s):

Chen Xu Zhao ◽

Xin Guo ◽

Tao Deng ◽

Ling Li ◽

Ze Wen Liu

Keyword(s):

Actuation Voltage ◽

Waveform Design ◽

Practical Case ◽

Voltage Waveform ◽

Mems Switches ◽

Mems Switch ◽

Simulation Based ◽

Speed Up ◽

Bouncing Effect

This paper presents an efficient methodology for automated optimal tailoring actuation voltage waveform of MEMS switches aiming at eliminating the detrimental contact bouncing effect to speed up the switching process and improve the mechanical reliability. This is a simulation-based approach where genetic algorithm (GA) is used in combination with a dedicated mechanical model of MEMS switch to derive optimal actuation waveform. The proposed technique has been implemented in SystemC-A, which is extremely well suited for complex modeling, implementation of post-processing of simulation results and optimization algorithms. Effectiveness of proposed approach is corroborated by a practical case study of automated actuation waveform design for a prefabricated DC-contact MEMS switch. The experimental results show that the switching time of the switch by employing optimized actuation voltage waveform is dramatically reduced to 60μs from 95μs, while the bouncing effect is successfully eliminated.

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Design of H-shaped low actuation-voltage RF-MEMS switches

2006 Asia-Pacific Microwave Conference ◽

10.1109/apmc.2006.4429697 ◽

2006 ◽

Cited By ~ 9

Author(s):

Anatoliy Batmanov ◽

Ehab K. I. Hamad ◽

Edmund P. Burte ◽

Abbas S. Omar

Keyword(s):

Rf Mems ◽

Actuation Voltage ◽

Mems Switches ◽

Rf Mems Switches

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RF-MEMS Application to RF Tuneable Circuits

Advances in Science and Technology ◽

10.4028/www.scientific.net/ast.100.100 ◽

2016 ◽

Vol 100 ◽

pp. 100-108

Author(s):

Roberto Sorrentino ◽

Paola Farinelli ◽

Alessandro Cazzorla ◽

Luca Pelliccia

Keyword(s):

Communication Systems ◽

Satellite Communication ◽

Rf Mems ◽

Low Loss ◽

Micro Electro Mechanical Systems ◽

Mems Switches ◽

High Linearity ◽

Technological Developments ◽

Intermodulation Distortions ◽

Complex Circuits

The bursting wireless communication market, including 5G, advanced satellite communication systems and COTM (Communication On The Move) terminals, require ever more sophisticated functions, from multi-band and multi-function operations to electronically steerable and reconfigurable antennas, pushing technological developments towards the use of tunable microwave components and circuits. Reconfigurability allows indeed for reduced complexity and cost of the apparatuses. In this context, RF MEMS (Micro-Electro-Mechanical-Systems) technology has emerged as a very attractive solution to realize both tunable devices (e.g. variable capacitors, inductors and micro-relays), as well as complex circuits (e.g. tunable filters, reconfigurable matching networks and reconfigurable beam forming networks for phased array antennas). High linearity, low loss and high miniaturization are the typical advantages of RF MEMS over conventional technologies. Micromechanical components fabricated via IC-compatible MEMS technologies and capable of low-loss filtering, switching and frequency generation allow for miniaturized wireless front-ends via higher levels of integration. In addition, the inherent high linearity of the MEMS switches enables carrier aggregations without introducing intermodulation distortions. This paper will review the recent advances in the development of the RF MEMS to RF tunable circuits and systems.

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