RF MEMS DPDT Switch Using Novel Simulated Seesaw Design

This paper investigates an RF MEMS (Radio Frequency Micro Electro-Mechanical System) switch from DC to 5.8 GHz switching, for use in mobile communications systems and devices. The RF MEMS switch uses a novel seesaw design to create a Double-Pole Double-Throw (DPDT) Switch which increases the capabilities of the seesaw design structure. A low Switching supply voltage with high RF isolation was achieved during its development. After looking at other available seesaw designs, it was discovered that an improvement could be attained by adding additional contacts. An improved concept over existing Single-Pole Single-Throw (SPST) seesaw switches was achieved by using a DPDT switch with a set of upper and lower contacts at each side of the seesaw. To conform to the Microscale, from 1 μm – 100 μm, a length of 41μm was chosen to provide an adequate size for fabrication. Copper Bulk General (Cu) was chosen for the pivot material due to its good electrical conductivity and sufficient flexibility for elastic recovery. A working simulation was achieved without compromising the ‘Air-Gap’ between the contacts, which retains high isolation when the switch is open-circuited. The electrostatic supply voltage has been significantly reduced to a value which is closer to that used in mobile devices.

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Fabrication Of Flat RF MEMS Switch Membrane By Minimizing Of Stress Gradients In The Au Membrane Structure

MRS Proceedings ◽

10.1557/proc-741-j5.2 ◽

2002 ◽

Vol 741 ◽

Cited By ~ 1

Author(s):

Jong-Seok Kim ◽

Hoon Song ◽

Jin Woo Cho ◽

Eun Sung Lee ◽

Sun Hee Park ◽

...

Keyword(s):

Membrane Structure ◽

Rf Mems ◽

Stress Gradient ◽

Micro Electro Mechanical System ◽

Driving Voltage ◽

Rf Mems Switch ◽

Broad Bandwidth ◽

Mems Switch ◽

Rf Systems ◽

Low Insertion Loss

ABSTRACTRF MEMS(Micro-Electro-Mechanical-System) switch technology is one of powerful solution for future RF systems. This technology provides low insertion loss, High linearity and broad bandwidth. Wide driving membrane used MEMS switch can reduce driving voltage but it is easy to bend because of the stress gradient. In order to solve this problem we fabricated Au cantilever in various sputtering condition and various substrate materials. As a result of this experiment, we fabricated cantilever which was bent within 1 um, with 2 um thickness and 340 um length. We applied this condition to RF MEMS switch and we fabricated switch membrane within 1 um bend, under 10MPa stress gradient.

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Design and Performance Analysis of Low Pull – in Voltage RF MEMS Shunt Switch for Millimeterwave Therapy, IoT and 5G Applications

10.21203/rs.3.rs-434735/v1 ◽

2021 ◽

Author(s):

Srinivasa rao k ◽

P. Ashok Kumar ◽

Girija Srav ◽

Koushik Guha

Keyword(s):

Communication Systems ◽

Rf Mems ◽

Wave Spectrum ◽

Signal Propagation ◽

Micro Electro Mechanical System ◽

Millimetre Wave ◽

Smart Systems ◽

Mems Switch ◽

Rf Devices ◽

And Performance

Abstract Recent Advancements in the wireless communication systems utilizes miniaturized devices based on Micro – Electro – Mechanical System technology for present and future 5G wireless applications. Now a days, RF devices are utilizing the frequencies upto 30 GHz and a huge traffic in signal propagation occurs which leads to the slow data rate. In other hand, there is a huge spectrum available in the millimetre wave frequency range of 30 – 300 GHz. The millimetre wave spectrum is attractive for development of smart systems based on 5G technology. In this paper, A low pull – in voltage capacitive type RF MEMS switch is proposed to operate at the frequencies above 30 GHz. The switch is proposed with new iterative meandering technique where span length of each section in meanders differs and dependable with first section. A low pull – in voltage of 1.8V is achieved with large capacitance ratio of 63. The switch exhibits low insertion loss of -0.24 dB at 41 GHz and possess high isolation of -46.7 dB at 38 GHz. The design is validated by comparing the theoretical and simulated results and the switch can be efficiently utilized for millimeterwave applications.

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Uncertainty Quantification of Pull-In Phenomenon in Capacitive RF-MEMS

Volume 7: 5th International Conference on Micro- and Nanosystems; 8th International Conference on Design and Design Education; 21st Reliability, Stress Analysis, and Failure Prevention Conference ◽

10.1115/detc2011-47260 ◽

2011 ◽

Cited By ~ 1

Author(s):

Sanjay Mathur ◽

Lin Sun ◽

Shankhadeep Das ◽

Dimitrios Peroulis ◽

Andrew Kovacs ◽

...

Keyword(s):

Uncertainty Quantification ◽

Rf Mems ◽

Uncertainty Propagation ◽

Process Variations ◽

Micro Electro Mechanical System ◽

Immersed Boundary ◽

Membrane Thickness ◽

Electrostatically Actuated ◽

Mems Switch ◽

Estimation Uncertainty

The goal of this paper is to elucidate the effects of device geometry and fabrication process variations on the statistical pull-in performance of an electrostatically-actuated capacitive radio frequency micro electro-mechanical system (RF-MEMS) switch through the use of uncertainty quantification. The prediction of switch dynamics and pull-in voltage involves the coupled interaction of elastodynamics, fluid dynamics, and electrostatics. A comprehensive computational framework based on the finite volume method (FVM) is developed to account for these effects. The immersed boundary method (IBM) is employed to couple the fluid, structure and electrostatics. A population of switches is fabricated, and geometry and material properties measured; these measurements provide the probabilistic input information needed for uncertainty quantification. Deterministic simulations are first made for a specific device, and the gap-versus-voltage and pull-in voltage predicted compare favorably with measurements and theoretical estimation. Uncertainty quantification of dynamic pull-in is performed next, using the stochastic collocation method for uncertainty propagation. Probability density functions (PDFs) of pull-in voltage and gap-versus-time are computed. The primary determinants of uncertainty in pull-in voltage are found to be the membrane thickness and gap size, with uncertainty in residual stress having a relatively small effect.

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Design and simulation of millimeter wave reconfigurable antenna using iterative meandered RF MEMS switch for 5G mobile communications

Microsystem Technologies ◽

10.1007/s00542-019-04606-w ◽

2019 ◽

Vol 26 (7) ◽

pp. 2267-2277 ◽

Cited By ~ 3

Author(s):

P. Ashok Kumar ◽

K. Srinivasa Rao ◽

K. Girija Sravani

Keyword(s):

Millimeter Wave ◽

Mobile Communications ◽

Rf Mems ◽

Reconfigurable Antenna ◽

Rf Mems Switch ◽

Mems Switch ◽

5G Mobile Communications

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Optimization of Scattering Parameters through Numerical Investigation of One-bit RF MEMS Switch over Ku, K and Ka Band

Micro and Nanosystems ◽

10.2174/1876402912999201102200350 ◽

2020 ◽

Vol 12 ◽

Author(s):

Pampa Debnath ◽

Ujjwal Mondal ◽

Arpan Deyasi

Keyword(s):

Transmission Line ◽

Numerical Investigation ◽

Line Width ◽

Insertion Loss ◽

Return Loss ◽

Rf Mems ◽

Rf Mems Switch ◽

Ka Band ◽

Mems Switch ◽

Overlap Area

Aim:: Computation of loss factors for one-bit RF MEMS switch over Ku, K and Ka-band for two different insulating substrates. Objective:: Numerical investigation of return loss, insertion loss, isolation loss are computed under both actuated and unactuated states for two different insulating substrates of the 1-bit RF MEMS switch, and corresponding up and down-capacitances are obtained. Methods:: The unique characteristics of a 1-bit RF MEMS switch of providing higher return loss under both actuated and unactuated states and also of isolation loss with negligible insertion loss makes it as a prime candidate for phase shifter application. This is presented in this manuscript with a keen focus on improvement capability by changing transmission line width, and also of overlap area; where dielectric constant of the substrate also plays a vital role. Results:: The present work exhibits very low down-capacitance over the spectrum whereas considerable amount of up-capacitance. Also when overall performance in terms of all loss parameters are considered, switch provides very low insertion loss, good return loss under actuated state and standard isolation loss. Conclusion:: Reduction of transmission line width of about 33% improved the performance of the switch by increasing isolation loss. Isolation loss of -40 dB is obtained at actuated condition in higher microwave spectra for SiO 2 at higher overlap area. Down capacitance of ~ 1dB is obtained which is novel as compared with other published literature. Moreover, a better combination of both return loss, isolation loss and insertion loss are reported in this present work compared with all other published data so far.

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