A new MEMS based variable capacitor with wide tunability, high linearity and low actuation voltage

Afrang, Saeid; Mobki, Hamed; Sadeghi, Mostafa; Rezazadeh, Ghader

doi:10.1016/j.mejo.2014.11.006

Cited by 13 publications

(7 citation statements)

References 13 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Microelectromechanical (MEM) parallel-plates based micro-capacitors have been widely used in communication transceivers [5] owning high tunability because of numerous reasons: the ease of implementation as simple tuning mechanisms, their low area consumption, their high quality factor and straightforwardness in their fabrication. Indeed, there are three major techniques to possibly increase the tunability of parallel-plates micro-capacitors:  Regulation of the electrodes initial gap distance [12][13][14],  Optimization of the effective actuated parallel-plates area [15,16], and  the dielectric displacement method [5,17].…”

Section: Introductionmentioning

confidence: 99%

On the implementation of adaptive sliding mode robust controller in the stabilization of electrically actuated micro-tunable capacitor

et al. 2020

Self Cite

View full text Add to dashboard Cite

Parallel-plates based micro-tunable capacitors are known to have low travel range, which worsen as going even lower in terms of their initials gap sizes. Such conditions have put strict requirements on the operation of such designs and hence hindering their use in numerous practical applications requiring high tunability. This work is proposed to examine the possibility to implement a closed-loop control strategy to increase the maximum capacitance and therefore tunability of micro tunable capacitors. The suggested control strategy is implemented on an electrostatically actuated parallel-plates (one stationary and one movable) based micro-capacitor and had an objective to stabilize the movable electrode when it is close to the fixed one for the sake of maximizing its maximum capacitance and possibly improving its overall tunability. Robustness of the micro-capacitor to the so-called pull-in phenomenon (short-circuit instability) when using the closed loop control scheme is studied. Indeed, an adaptive sliding mode controller is designed to compensate the effects of uncertainty, disturbance and eliminate any possibility for chattering phenomenon. The controller proficiencies in terms of stabilizing the micro-capacitor and its robustness to uncertainty as well as disturbance have been thoroughly examined. Furthermore, the effects of the control parameters on the behavior of micro-capacitor, such as overshoot, settling time, steady state error, robustness to uncertainty, external disturbances and to the chattering phenomenon, have been completely inspected. The obtained results indicated satisfactory proficiency and trustworthiness of the proposed control strategy to achieve high level of tunability and maximum capacitance.

show abstract

Section: Introductionmentioning

confidence: 99%

On the implementation of adaptive sliding mode robust controller in the stabilization of electrically actuated micro-tunable capacitor

et al. 2020

Self Cite

View full text Add to dashboard Cite

show abstract

“…Due to the nonlinear nature of the electrostatic force applied between the two capacitive electrodes as well as the pull-in instability present in the system, the relative displacement between the electrodes cannot exceed a certain distance. Considerable relative displacements between capacitive electrodes, for example in tunable micro capacitors, is of great importance [13,14].…”

Section: Introductionmentioning

confidence: 99%

“…To achieve this end, some modification implemented in the design and fabrication process of the micro capacitors [2,13,14]. These changes complicated the design and construction process, as well as increased costs.…”

Section: Introductionmentioning

confidence: 99%

See 1 more Smart Citation

Multi input versus single input sliding mode for closed-loop control of capacitive micro structures

et al. 2019

Self Cite

View full text Add to dashboard Cite

Considering the importance of closed-loop control for control of capacitive microstructures and the high capability of the sliding-mode controllers in control of nonlinear systems, the present study has investigated the closed-loop control of these structures using the sliding-mode controller. For this purpose, the sliding-mode controller was designed for single-and double-input cases, and the applied voltages between the capacitive electrodes was considered as the control inputs. The simulation results for both single-and double-input cases have been extracted and presented, and it was concluded that achieving an accurate control for the single input case is not always feasible given that the sign of the sliding surface changes and the control parameter assume positive definite values. Moreover, it has been shown that an accurate control could be achieved by employing the double-input controller without any limitations. The chattering phenomenon was also thoroughly studied in the initial controller design. To eliminate this phenomenon, a smooth variation has been applied to the switching of the sliding surface. In addition to tracking, the capacitive microstructure has been investigated to reduce the relative distance between the two electrodes (in order to increase the capacitive storage), and the obtained results have been presented.

show abstract

“…Simulating the mechanical behavior of these devices, particularly their static and dynamic behavior, is required for design and manufacturing purposes. Therefore, electrostatically actuated MEM/NEM devices such as, micro switches [1,2] micro-mirrors [3,4], nano-switches [5,6], nano-tweezers [7,8], micro capacitors [9][10][11], sensors [12,13], resonators [14,15] and oscillators [16,17] are widely designed, fabricated, used and analyzed.…”

Section: Introductionmentioning

confidence: 99%

Investigation of dynamic instability of three plates switch under step DC voltage actuation using modified couple stress theory

Fard

Gharechahi

Fard

et al. 2018

Lat. Am. j. solids struct.

Self Cite

View full text Add to dashboard Cite

In this paper dynamical instability of three-layer micro-switch under DC voltage actuation has been studied. Recent studies have used the classical beam theory while leaving out the length scale parameter. In this paper dynamic behavior of the switch has been investigated based on couple stress theory and considering the length scale parameter. To this end, governing dynamic equation of the micro switch has been extracted and presented. Considering the nonlinearity of governing equation due to the existence of electrostatic force, Galerkin method has been implemented to overcome this nonlinearity and solve the mentioned equation and obtain the dynamic response. Dynamic response of micro switch has been investigated with and without considering the damping effects. Variation of dynamic pull-in voltage versus micro beam length and primary gap between micro beam and stationary electrodes have been studied using couple stress and classic beam theory and obtained results have been compared to each other. Also dependency of dynamic pull-in voltage to damping factor has been studied with considering two theories. Furthermore switching time of micro switch have been determined and compared using couple stress and classic beam theories.

show abstract

A new MEMS based variable capacitor with wide tunability, high linearity and low actuation voltage

Cited by 13 publications

References 13 publications

On the implementation of adaptive sliding mode robust controller in the stabilization of electrically actuated micro-tunable capacitor

On the implementation of adaptive sliding mode robust controller in the stabilization of electrically actuated micro-tunable capacitor

Multi input versus single input sliding mode for closed-loop control of capacitive micro structures

Investigation of dynamic instability of three plates switch under step DC voltage actuation using modified couple stress theory

Contact Info

Product

Resources

About