Design, fabrication, characterization of micromachined capacitive shunt switches with low actuation voltages and low temperature packaging (original) (raw)
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Progress In Electromagnetics Research, 2006
A novel structure for the capacitive micromachined switches with low actuation voltage is proposed. In this structure both contact plates of the switch are designed as displaceable membranes. Two structures with similar dimensions and conditions, differing on only the number of the displaceable beams are analytically investigated as well as simulated using ANSYS software. The obtained results indicate about 30% reduction in actuation voltage from the conventional single beam to our proposed double beam structure. The stress on the beam due to the actuation voltage is also reduced increasing the switching life time. The dynamic simulation results in switching time of 6.5 µsec compared to the 8.9 µsec of the analytical results. It can be implemented by the well established surface micromachining for RF applications.
IAETSD-Design and Analysis of a Novel Low Actuated Voltage RF MEMS Shunt Capacitive Switch
This Paper presents design, analysis, proposed fabrication process and simulation of a novel low actuated voltage shunt capacitive RF MEMS Switch. The Air gap in between the membrane and CPW signal line is 1.5 µm. The lowest actuation voltage of switch is 3 Volts. The proposed fixedfixed flexures beam structure provides excellent RF Characteristics (Isolation -43 dB at 28 GHZ and insertion loss -0.12 dB at 28 GHZ).
Design of H-shaped low actuation-voltage RF-MEMS switches
2006 Asia-Pacific Microwave Conference, 2006
Low actuation-voltage and high reliable microelectromechanical systems (MEMS) shunt capacitive and shunt resistive switches are in this paper proposed. Electrostatic-mechanical coupling using finite element method (FEM) and full-wave electromagnetic (EM) analyses have been performed. The mechanical design of a low spring-constant switch structure has been optimized by calculating the dependence of the actuation voltage on the membrane shape, material properties and geometrical sizes. The proposed switches, based on Al metallization membrane, show a pull-in voltage around 7 and 13 Volts with 0 and 20 MPa residual stresses, respectively. The simulated insertion losses are less than 0.25 dB up to 40GHz with a return loss of about 20 dB in the ONstate. The isolations in the OFF-state for the capacitive-switch are greater than 20 and 35 dB at 12 and 40 GHz, respectively. The shunt resistive switch theoretically works from zero frequency with isolation greater than 25 dB up to 40 GHz. The fabrication of those switches is compatible with standard CMOS technology and they are in process. Index Terms -Low-actuation voltage, MEMS, Pull-in, RF MEMS switch.
HELIX
The electromagnetic and the electromechanical characteristics of the radio frequency micro-electro-mechanicalsystem (RF MEMS) switches for high-frequency applications are the critical performance metrics that need to optimize. Performance indices of the RF MEMS switches such as isolation, insertion loss, pull-in voltage, holddown voltage, reliability are dependent on types and properties of conducting and insulating materials that are used in the construction of switch. This article proposes the design and analysis of the two terminal capacitive shunt switches built on a coplanar waveguide (CPW) for applications in subsets of Ka-and V-Band frequency range. The proposed switch used a fixed-fixed gold membrane with the low-spring constant uniform single meander flexures support and achieved a low pull-in voltage of 5.1 Volts. An impact of the variation of the geometric parameter trade-offs like conducting membrane height, dielectric material height, and the air gap between the membrane and the dielectric materials like Silicon Nitride (Si3N4) and Hafnium Dioxide (HfO2) are studied to investigate RF and electromechanical performance of the switch.