Improved Sensitivity in the Thermal Investigation of Polymeric Nanophases by Measuring the Resonance Frequency Shift using an Atomic Force Microscope

ABSTRACTIn this work, we present a reliability and stability study of doped hydrogenated amorphous silicon (n+-a-Si:H) thin-film silicon MEMS resonators. The n+-a-Si:H structural material was deposited using radio frequency plasma enhanced chemical vapor deposition (RF-PECVD) and processed using surface micromachining at a maximum deposition temperature of 110 ºC. n+-a-Si:H resonant bridges can withstand the industry standard of 1011 cycles at high load with no structural damage. Tests performed up to 3x1011 cycles showed a negligible level of degradation in Q during the entire cycling period which in addition shows the high stability of the resonator. In measurements both in vacuum and in air a resonance frequency shift which is proportional to the number of cycles is established. This shift is between 0.1 and 0.4%/1x1011 cycles depending on the applied VDC. When following the resonance frequency in vacuum during cyclic loading, desorption of air molecules from the resonator surface is responsible for an initial higher resonance frequency shift before the linear dependence is established.

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A technique for highly sensitive detection of mercury ions using DNA-functionalized gold nanoparticles and resonators based on a resonance frequency shift

Journal of Mechanical Science and Technology ◽

10.1007/s12206-018-0128-y ◽

2018 ◽

Vol 32 (2) ◽

pp. 799-804 ◽

Cited By ~ 7

Author(s):

Jinho Chu ◽

Chanho Park ◽

Kuewhan Jang ◽

Jae Hong Shim ◽

Sungsoo Na

Keyword(s):

Gold Nanoparticles ◽

Resonance Frequency ◽

Frequency Shift ◽

Sensitive Detection ◽

Mercury Ions ◽

Functionalized Gold Nanoparticles ◽

Resonance Frequency Shift ◽

Highly Sensitive ◽

Highly Sensitive Detection

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Correcting heat-induced chemical shift distortions in proton resonance frequency-shift thermometry

Magnetic Resonance in Medicine ◽

10.1002/mrm.25899 ◽

2015 ◽

Vol 76 (1) ◽

pp. 172-182 ◽

Cited By ~ 10

Author(s):

Pooja Gaur ◽

Ari Partanen ◽

Beat Werner ◽

Pejman Ghanouni ◽

Rachelle Bitton ◽

...

Keyword(s):

Chemical Shift ◽

Resonance Frequency ◽

Frequency Shift ◽

Proton Resonance Frequency ◽

Proton Resonance ◽

Proton Resonance Frequency Shift ◽

Resonance Frequency Shift

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Investigation on Resonance Effects of Closely Resonating Nano-Pillars Attached to SAW Resonator

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.403-408.1183 ◽

2011 ◽

Vol 403-408 ◽

pp. 1183-1187

Author(s):

N. Ramakrishnan ◽

Harshal B. Nemade ◽

Roy Paily Palathinkal

Keyword(s):

Acoustic Wave ◽

Resonance Frequency ◽

Frequency Shift ◽

Fem Simulation ◽

Mass Loading ◽

Loading Effect ◽

Resonance Effects ◽

Additional Information ◽

Resonance Frequency Shift ◽

Small Change

Surface acoustic wave (SAW) sensors form an important class of micro sensors in the microelecto mechanical systems (MEMS) family. Mass loading effect of a sensing medium is one of the prime sensing principles in SAW sensors. Recently we reported mass loading effect of high aspect ratio nano-pillars attached to a SAW resonator. We observed increase in resonance frequency of the SAW resonator in addition to the general mass loading characteristics. We concluded that when the resonance frequency of the pillar is equal to the SAW resonator frequency, the resonance frequency shift caused by mass loading of pillar tends to a negligible value. When such resonating pillars are used as sensing medium in SAW sensors, even a very small change in the dimension of the pillar will offer significant resonance frequency shift. Accordingly, high sensitive SAW sensors can be developed. However in practice it’s quite difficult to manufacture nano-pillars with accurate dimensions such that they resonate with SAW resonator. There is more probability that the pillars may closely resonate with SAW device and offer mass loading. In the present work we have extended our earlier work and performed finite element method (FEM) simulation to study the insight physics of the closely resonating pillars and their effects on acoustic wave propagating on SAW substrate. In this paper we present the discussion on the resonance effects of typical closely resonating pillars on resonance frequency spectrum of the SAW resonator and observations in the pressure wave at the contact surface of the pillar and SAW resonator substrate. It is observed that when the nano-pillars closely resonate with SAW resonator, the pillar oscillations combine with waves propagating in the substrate and introduce beat frequencies. The results and discussion of this paper adds additional information in designing SAW based coupled resonating systems.

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CO Gas-Induced Resonance Frequency Shift of ZnO-Functionalized Microcantilever in Humid Air

Journal of Nanomaterials ◽

10.1155/2017/4824607 ◽

2017 ◽

Vol 2017 ◽

pp. 1-7 ◽

Cited By ~ 5

Author(s):

Lia Aprilia ◽

Ratno Nuryadi ◽

Dwi Gustiono ◽

Nurmahmudi ◽

Arief Udhiarto ◽

...

Keyword(s):

Carbon Monoxide ◽

Zinc Oxide ◽

Water Vapor ◽

Resonance Frequency ◽

Frequency Shift ◽

Hydrothermal Method ◽

Gas Flow ◽

Humid Air ◽

Resonance Frequency Shift ◽

Co Gas

Resonance frequency shift of a zinc oxide- (ZnO-) functionalized microcantilever as a response to carbon monoxide (CO) gas has been investigated. Here, ZnO microrods were grown on the microcantilever surface by a hydrothermal method. The measurement of resonance frequency of the microcantilever vibrations due to the gas was carried out in two conditions, that is, gas flow with and without air pumping into an experiment chamber. The results show that the resonance frequency of the ZnO-functionalized microcantilever decreases because of CO in air pumping condition, while it increases when CO is introduced without air pumping. Such change in the resonance frequency is influenced by water vapor condition, and a possible model based on water-CO combination was proposed.

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