Showing papers by "Kamaljit Rangra published in 2017"
TL;DR: In this paper, CdO thin films were grown by e-beam evaporation technique on glass, indium tin oxide (ITO), fluorine-doped tin dioxide (FTO), and silicon (Si) wafer.
34 citations
TL;DR: In this paper, a low voltage driven RF MEMS capacitive switch with the introduction of perforations and reinforcement is proposed, which reduces the pull-in voltage from 70 V to 16.2 V and the magnitude of deformation from 8 µm to 1 µm.
Abstract: Variation in actuation voltage for RF MEMS switches is observed as a result of stress-generated buckling of MEMS structures. Large voltage driven RF-MEMS switches are a major concern in space bound communication applications. In this paper, we propose a low voltage driven RF MEMS capacitive switch with the introduction of perforations and reinforcement. The performance of the fabricated switch is compared with conventional capacitive RF MEMS switches. The pull-in voltage of the switch is reduced from 70 V to 16.2 V and the magnitude of deformation is reduced from 8 µm to 1 µm. The design of the reinforcement frame enhances the structural stiffness by 46 % without affecting the high frequency response of the switch. The measured isolation and insertion loss of the reinforced switch is more than 20 dB and 0.4 dB over the X band range.
25 citations
TL;DR: In this article, the infrared absorption characteristics of near atmospheric, N2 ambient DC sputtered Au thin films are studied for handling and patterning of thermally grown Au-black coating and the steady state temperature response of sputtered film is examined using nondestructive thermal imaging method under external heating of the detector array.
8 citations
09 Jan 2017
TL;DR: In this article, three different loss sources are identified and a thin film bulk acoustic resonator (FBAR) is designed and simulated in order to reduce the losses through the anchor reduction, which leads the FBAR structure to vibrate more freely at the resonance.
Abstract: Thin film bulk acoustic resonator (FBAR) higher quality factor (Q) provides steep skirt and low insertion losses in the pass band. In this paper, three different loss sources are identified and FBAR is design and simulated in order to reduce the losses. Firstly, the FBAR’s top electrode is simulated for the areas of 150 × 150, 300 × 300 and 400 × 400 μm2 and the quality factor is improved as the area increased to 102, 432.6 and 743.7 respectively. The impedance of the FBAR is reduced as the area of the electrode is increased. Secondly, the anchor width is reduced from 60 to 45 μm and the quality factor is increased from 341 to 432.6 respectively. The losses through the anchor reduce as the anchor reduces. Electrode area and anchor area simulation are showing the notable effect and no other paper is reported for the comparison. Thirdly, the damping factor coefficient (β) is varied as 4.7e−14, 3.84e−14 and 2.5e−14. The quality factor is increased as the damping factor reduces and reported as 283.2, 341.2 and 444.5 respectively. The damping reduction leads the FBAR structure to vibrate more freely at the resonance. The losses through damping are reduced and more energy has stored at the resonance so it increases the quality factor.
8 citations
TL;DR: In this paper, the authors used polyimide as a support layer to achieve acoustic wave confinement in a Film Bulk Acoustic Resonator (FBAR) and achieved a Q-factor of 1.8∗10 28.
3 citations
TL;DR: In this article, a film bulk acoustic resonator (FBAR) was used as a gas sensor for DCM sensing, which has a high quality factor of 1209 at the resonance and shows a coupling coefficient of 7.51% for the 0.7-μm-thick PZE layer.
Abstract: The application of a film bulk acoustic resonator (FBAR) as a gas sensor is presented here. Zinc Oxide is used as a piezoelectric (PZE) material for the resonator and a Bragg reflector is made of Molybdenum and Silicon dioxide in proposed Solidly Mounted FBAR. The structure offers a high quality factor of 1209 at the resonance and shows a coupling coefficient of 7.51% for the 0.7-μm-thick PZE layer. To make it capable of working as a gas sensor, an additional sensitive layer for adsorption is used. A 0.51-μm-thin film of polymer-sensitive layer (polyisobutylene, PIB) is used on the top electrode. The adsorption of CH2Cl2 (dichloromethane, DCM) prompts the change in density of the PIB layer, which causes the change in resonance frequency of the FBAR. The simulation results have shown the sensitivity of 450 Hz/ppm for gas sensing for the above-mentioned structure. The sensitivity of the sensor depends on the characteristic frequencies of the device, which are further the function of the thickness of the resonating structure. No involvement of a harsh etching process in fabrication, in addition to immense sensitivity and quality factor, makes this sensor relevant for DCM sensing.
2 citations
12 Dec 2017
TL;DR: In this paper, a large stroke surface micromachined micromirror platform actuated using inverse-series-connected (ISC) bimorph actuator is presented, which is capable of producing both piston and tip-tilt motion by application of voltage to Aluminum layer which acts as a constituent layer of ICS bimomorph and an electrical heater simultaneously.
Abstract: This paper presents a large stroke surface micromachined micromirror platform actuated using inverse-series-connected (ISC) bimorph actuator. The proposed structure is designed using four symmetric ICS bimorph actuator made up of Aluminum and Silicon Dioxide and a micromirror plate of sandwiched layer of SiO2 and Aluminum The platform is capable of producing both piston and tip-tilt motion by application of voltage to Aluminum layer which acts as a constituent layer of ICS bimorph and an electrical heater simultaneously. With a mirror plate size of 500 × 500 µm2, the maximum displacement is 100 µm in piston mode and 69 µm in tip-tilt mode at 0.2 V. The micromirror is capable of scanning with resonance frequencies at 4.31 and 6.70 kHz in piston and torsional mode respectively.
12 Dec 2017
TL;DR: In this paper, a low cost method for depositing the hard alloy materials for electrical contact as well as MEMS structure application was reported, where the alloy formation was performed using a novel Electroplating method of synthesis.
Abstract: In this paper, we have reported a low cost method for depositing the hard alloy materials for electrical contact as well as MEMS structure application. Conventional methods of deposition like co-sputtering, e-beam PVD, etc. required a high running cost and had a high waste generation due to poor selectivity of deposition. The alloy formation was performed using a novel Electroplating method of synthesis. Au–Co alloy is made using a single bath electrodeposition for Au–Co thin films. XRD peaks analysis was used to confirm the alloy formation. AFM analysis was used to study the grains size, and surface roughness and the hardness measurement was performed using micro-indentation. The less surface roughness and high strength (Hardened) gold alloy formation were observed for a neutral pH (6.6 pH) Au–Co Alloy electroplating conditions. The low pH (4.0 pH) solution results to higher surface roughness while higher pH of the solution was not suitable for Au electroplating.