Design and Modelling of Novel Linearly Tunable Capacitors

2006 ◽  
Author(s):  
Mohammad Shavezipur ◽  
Amir Khajepour ◽  
Seyed Mohammad Hashemi
Keyword(s):  
High Sensitivity ◽  
Variable Stiffness ◽  
Lower Sensitivity ◽  
High Q ◽  
Tunable Capacitors ◽  
High Tunability ◽  
Capacitance Voltage ◽  
Low Sensitivity ◽  
Q Factors ◽  
Very High

MEMS-based tunable capacitors with electrostatic actuation are well-known for their wide tuning ranges, high Q-factors, fast responses, and small sizes. However, tunable capacitors exhibit very high sensitivity near pull-in voltage which counters the concept of tunability. In this research, two novel designs are presented that improve the high sensitivity in capacitance-voltage (C-V) curve. In the first design, the nonlinear deformation of supporting beams is studied to develop a new nonlinear spring. The variable stiffness coefficients of such springs improve the linearity of the C-V curve, and by delaying the pull-in, the maximum tunability is also increased without using complex geometries. In the second design, an asymmetric non-parallel-plate capacitor is introduced, in which the C-V response has lower sensitivity at high voltages. The design concept can be applied to highly tunable capacitors to improve the sensitivity and maintain high tunability. The numerical results demonstrate low sensitivity and high linearity and tunability for the new designs.

Novel Highly Tunable MEMS Capacitors With Flexible Structure and Linear C-V Response

2007 ◽  
Author(s):  
Mohammad Shavezipur ◽  
Seyed Mohammad Hashemi ◽  
Amir Khajepour
Keyword(s):  
Vertical Movement ◽  
Moving Plate ◽  
Rf Systems ◽  
Tunable Capacitors ◽  
High Tunability ◽  
Highly Sensitive ◽  
Capacitance Voltage ◽  
Middle Node ◽  
Low Sensitivity ◽  
Q Factors

MEMS parallel-plate tunable capacitors are widely used in different areas such as tunable filters, resonators and communications (RF) systems for their simple structures, high Q-factors and small sizes. However, these capacitors have relatively low tuning range (50%) and are subjected to highly sensitive and nonlinear capacitance-voltage (C-V) responses. In this paper novel designs are developed which have C-V responses with high linearity and tunability and low sensitivity. The designs use the flexibility of the moving plates. The plate is segmented to provide a controllable flexibility. Segments are connected together at end nodes by torsional springs. Under each node there is a step which limits the vertical movement of that node. An optimization program finds the best set of step heights that provides the highest linearity. Two numerical examples of three-segmented- and six-segmented-plate capacitors verify that the segmentation of moving plate can considerably improve the linearity without decreasing the conventional tunability. A two-segmented-plate capacitor is then designed for standard processes which cannot fabricate steps of different heights. The new design uses a flexible step (spring) under middle node. The simulation of a capacitor with flexible middle step, designed for PolyMUMPs process, demonstrates a C-V response with high tunability and linearity and low sensitivity.

A Novel Highly Tunable Butterfly-Type MEMS Capacitor

2007 ◽  
Author(s):  
Mohammad Shavezipur ◽  
Amir Khajepour ◽  
Seyed Mohammad Hashemi
Keyword(s):  
Electrostatic Force ◽  
Actuation Voltage ◽  
Tunable Capacitor ◽  
Tunable Capacitors ◽  
High Tunability ◽  
Structural Rigidity ◽  
Highly Sensitive ◽  
Capacitance Voltage ◽  
Nodal Displacements ◽  
Q Factors

MEMS parallel-plate tunable capacitors are widely used in different devices such as tunable filters and resonators because of their simple structures, high Q-factors and small sizes. However, these capacitors have low tuning range with nonlinear and highly sensitive capacitance-voltage (C-V) responses. In this paper the development of novel tunable capacitor designs exhibiting highly linear C-V responses, is presented. The designs use segmentation technique to produce lumped flexibility in capacitor’s structure. A numerical model is developed to simulate the behavior of the capacitor. When a actuation voltage is applied, the structural rigidity of the plate produces resistive force which balances the electrostatic force, causes nodal displacements and changes the capacitance. It is shown that by optimizing the shape of segments (from rectangular to trapezoidal) and adding flexible steps located under the segments, a low sensitive linear C-V response could be achieved, while maintaining high tunability. The results of numerical simulation for the capacitors designed for PolyMUMPs process demonstrate that by optimization of the segments shape and structural stiffness a combination of high tunability over 100% and highly linear C-V response is achievable.

Realization of High-Q Fano Resonances in Ceramic Dielectric Metamaterials for Sensing Applications

2013 ◽  
Vol 2013 (CICMT) ◽  
pp. 000087-000093
Author(s):  
Elena Semouchkina ◽  
Arash Hosseinzadeh ◽  
George Semouchkin
Keyword(s):  
Numerical Experiments ◽  
Microstrip Line ◽  
High Sensitivity ◽  
Fano Resonances ◽  
High Q ◽  
Sensing Applications ◽  
Microwave Sensor ◽  
Q Factors ◽  
New Applications ◽  
Very High

Ceramic all-dielectric metamaterials are found to support very high Q resonances of the Fano-type, which until recently were largely attributed to the atomic physics phenomena. It is shown that proper arrangement of ceramic resonators in the metamaterial array allowsd for obtaining Q factors up to 15000. Thus high Q factors could be employed for new applications, in particular, for advanced sensing. An opportunity to design compact arrays that could be incorporated in a microwave sensor fed by a microstrip line is demonstrated. Numerical experiments have confirmed that Fano resonances in such arrays conserve high sensitivity to the dielectric permittivity of the controlled media.

scholarly journals Deformed microcavities with very high Q-factors and directional farfield emission

2020 ◽  
Vol 238 ◽  
pp. 01006
Author(s):  
Arne Behrens ◽  
Martí Bosch ◽  
Martina Hentschel ◽  
Stefan Sinzinger
Keyword(s):  
Surface Roughness ◽  
State Of The Art ◽  
Whispering Gallery Mode ◽  
Q Factor ◽  
Tapered Fiber ◽  
High Q ◽  
Whispering Gallery ◽  
Q Factors ◽  
Very High

We report the design and optimized fabrication of deformed whispering gallery mode resonators in silica with solely ICP-RIE. This allows us to control the morphology of the resonators more freely and results in low surface roughness. The light was coupled into the resonator using a state of the art tapered fiber approach and we determined the Q-factor in the range of 105

Rubella virus hemagglutination with human and animal erythrocytes: effect of age and trypsinization

1978 ◽  
Vol 7 (5) ◽  
pp. 442-447
Author(s):  
A N Ponzi ◽  
A Pugliese ◽  
P Pertusio
Keyword(s):  
Guinea Pig ◽  
Rubella Virus ◽  
Hemagglutination Inhibition ◽  
Animal Species ◽  
High Sensitivity ◽  
The Other ◽  
Low Sensitivity ◽  
Effect Of Age ◽  
Very High ◽  
Higher Sensitivity

Sensitivity to rubella virus hemagglutination differs considerably with newborn as opposed to adult erythrocytes (RBC) in several animal species. In humans, cord RBC are 16 times more sensitive to hemagglutination, whereas hemagglutination titers with newborn RBC are 6 to 16 times higher in chickens, mice, and rabbits. This higher sensitivity is, however, short-lived, and adult RBC values are observed 7 days after birth in mice. Trypsinization has no effect on newborn RBC, but increases sensitivity of adult RBC to that of neonatal RBC and tends to diminish differences among individuals. On the other hand, trypsinization does not further enhance the very high sensitivity of pigeon, duck, and goose RBC or the low sensitivity of both newborn and adult guinea pig RBC. Human cord RBC proved suitable for use in hemagglutination-inhibition tests, since they gave titers comparable to those obtained with other types of RBC and offered some advantages: by comparison with animal RBC, they did not require adsorption to remove nonspecific agglutinins; by comparison with adult human RBC, they did not need trypsinization.

Design of a metasurface-based dual-band Terahertz perfect absorber with very high Q-factors for sensing applications

2018 ◽  
Vol 416 ◽  
pp. 152-159 ◽  
Author(s):  
M. Janneh ◽  
A. De Marcellis ◽  
E. Palange ◽  
A.T. Tenggara ◽  
D. Byun
Keyword(s):  
Dual Band ◽  
Perfect Absorber ◽  
High Q ◽  
Sensing Applications ◽  
Q Factors ◽  
Very High

scholarly journals SHORELINE SENSITIVITY INDEX TO OIL SPILLS IN NUSA PENIDA MARINE PROTECTED AREA (MPA), BALI

2021 ◽  
Vol 15 (1) ◽  
pp. 47
Author(s):  
IPG Eka Handrayana Putra ◽  
Takahiro Osawa ◽  
I Wayan Gede Astawa Karang
Keyword(s):  
Marine Protected Area ◽  
Oil Spills ◽  
High Sensitivity ◽  
Tidal Range ◽  
Sensitivity Index ◽  
The West ◽  
Sensitivity Level ◽  
The Difference ◽  
Low Sensitivity ◽  
Very High

The Shoreline Sensitivity Index(SSI) is one crucial aspect to know in protecting the coast from all threats, including oil spills. This study aims to determine the shoreline's sensitivity for oil spills based on several oceanographic parameters: shoreline type, tidal range, slope, and wave high in Nusa Penida, Map Protection Area (MPA). The weight overlay method was employed to apply the geographic information system (GIS). Each parameter component was scored as five categories before the weighted overlay. The shoreline sensitivity level of Nusa Penida island is divided into five categories: very low sensitive, low sensitive, medium sensitive, high sensitive, and very high sensitive. As the results, the SSI was categorized during the east monsoons (from June to August) and during the west monsoons (from December to February) is at a low sensitivity level to very high sensitivity. SSI during east monsoons there is about 60.05% (627.33 ha) in the medium, 9.39% (98.11 ha) in the high, and 2.39% (24.99 ha) in the very high sensitive. The SSI during the west season is about 78.16% (816.95 ha) with the medium, 19.43% (203.11 ha) with the high, and 2.39% (24.99 ha) with the very high sensitive. The difference in wave height during east and west monsoons greatly affects the sensitivity level of the Nusa Penida coastal area. However, sensitivity level in Jungutbatu and Lembongan Villages are not affected by the east or west monsoons.Keywords: Shoreline Sensitivity; GIS; Nusa Penida; Oil Spill.

Sign in / Sign up

Export Citation Format

Share Document