A Novel MEMS Capacitive Microphone with Semiconstrained Diaphragm Supported with Center and Peripheral Backplate Protrusions

Audio applications such as mobile phones, hearing aids, true wireless stereo earphones, and Internet of Things devices demand small size, high performance, and reduced cost. Microelectromechanical system (MEMS) capacitive microphones fulfill these requirements with improved reliability and specifications related to sensitivity, signal-to-noise ratio (SNR), distortion, and dynamic range when compared to their electret condenser microphone counterparts. We present the design and modeling of a semiconstrained polysilicon diaphragm with flexible springs that are simply supported under bias voltage with a center and eight peripheral protrusions extending from the backplate. The flexible springs attached to the diaphragm reduce the residual film stress effect more effectively compared to constrained diaphragms. The center and peripheral protrusions from the backplate further increase the effective area, linearity, and sensitivity of the diaphragm when the diaphragm engages with these protrusions under an applied bias voltage. Finite element modeling approaches have been implemented to estimate deflection, compliance, and resonance. We report an 85% increase in the effective area of the diaphragm in this configuration with respect to a constrained diaphragm and a 48% increase with respect to a simply supported diaphragm without the center protrusion. Under the applied bias, the effective area further increases by an additional 15% as compared to the unbiased diaphragm effective area. A lumped element model has been also developed to predict the mechanical and electrical behavior of the microphone. With an applied bias, the microphone has a sensitivity of −38 dB (ref. 1 V/Pa at 1 kHz) and an SNR of 67 dBA measured in a 3.25 mm ´ 1.9 mm ´ 0.9 mm package including an analog ASIC.

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Surface state controlled ultrahigh selectivity and sensitivity for UV photodetectors based on individual SnO2 nanowires

Journal of Materials Chemistry C ◽

10.1039/c6tc02420c ◽

2016 ◽

Vol 4 (36) ◽

pp. 8399-8406 ◽

Cited By ~ 25

Author(s):

Haiping Shi ◽

Baochang Cheng ◽

Qiangsheng Cai ◽

Xiaohui Su ◽

Yanhe Xiao ◽

...

Keyword(s):

Light Intensity ◽

Bias Voltage ◽

Surface State ◽

High Performance ◽

Surface States ◽

Applied Bias ◽

Applied Bias Voltage ◽

Uv Photodetectors ◽

Sno2 Nanowires

Surface states are utilized for the development of high-performance photodetectors based on individual SnO2 nanowires. Their photodetectivity strongly depends on externally applied bias voltage and illuminated light intensity.

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High-performance magneto-rheological clutches for direct-drive actuation: Design and development

Journal of Intelligent Material Systems and Structures ◽

10.1177/1045389x211006902 ◽

2021 ◽

pp. 1045389X2110069

Author(s):

Sergey Pisetskiy ◽

Mehrdad Kermani

Keyword(s):

High Performance ◽

Degrees Of Freedom ◽

Dynamic Range ◽

Complete Analysis ◽

Mass Ratio ◽

Direct Drive ◽

Element Analysis ◽

Prototype Development ◽

Magneto Rheological ◽

Hall Sensors

This paper presents an improved design, complete analysis, and prototype development of high torque-to-mass ratio Magneto-Rheological (MR) clutches. The proposed MR clutches are intended as the main actuation mechanism of a robotic manipulator with five degrees of freedom. Multiple steps to increase the toque-to-mass ratio of the clutch are evaluated and implemented in one design. First, we focus on the Hall sensors’ configuration. Our proposed MR clutches feature embedded Hall sensors for the indirect torque measurement. A new arrangement of the sensors with no effect on the magnetic reluctance of the clutch is presented. Second, we improve the magnetization of the MR clutch. We utilize a new hybrid design that features a combination of an electromagnetic coil and a permanent magnet for improved torque-to-mass ratio. Third, the gap size reduction in the hybrid MR clutch is introduced and the effect of such reduction on maximum torque and the dynamic range of MR clutch is investigated. Finally, the design for a pair of MR clutches with a shared magnetic core for antagonistic actuation of the robot joint is presented and experimentally validated. The details of each approach are discussed and the results of the finite element analysis are used to highlight the required engineering steps and to demonstrate the improvements achieved. Using the proposed design, several prototypes of the MR clutch with various torque capacities ranging from 15 to 200 N·m are developed, assembled, and tested. The experimental results demonstrate the performance of the proposed design and validate the accuracy of the analysis used for the development.

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Influence of Applied Bias Voltage on the Composition, Structure, and Properties of Ti:Si-Codoped a-C:H Films Prepared by Magnetron Sputtering

Journal of Nanomaterials ◽

10.1155/2014/937068 ◽

2014 ◽

Vol 2014 ◽

pp. 1-7 ◽

Cited By ~ 3

Author(s):

Jinlong Jiang ◽

Qiong Wang ◽

Yubao Wang ◽

Zhang Xia ◽

Hua Yang ◽

...

Keyword(s):

Mechanical Properties ◽

Surface Roughness ◽

Magnetron Sputtering ◽

Bias Voltage ◽

Tribological Properties ◽

Structure And Properties ◽

Applied Bias ◽

Applied Bias Voltage ◽

Methane Mixture ◽

Composition Structure

The titanium- and silicon-codoped a-C:H films were prepared at different applied bias voltage by magnetron sputtering TiSi target in argon and methane mixture atmosphere. The influence of the applied bias voltage on the composition, surface morphology, structure, and mechanical properties of the films was investigated by XPS, AFM, Raman, FTIR spectroscopy, and nanoindenter. The tribological properties of the films were characterized on an UMT-2MT tribometer. The results demonstrated that the film became smoother and denser with increasing the applied bias voltage up to −200 V, whereas surface roughness increased due to the enhancement of ion bombardment as the applied bias voltage further increased. The sp3carbon fraction in the films monotonously decreased with increasing the applied bias voltage. The film exhibited moderate hardness and the superior tribological properties at the applied bias voltage of −100 V. The tribological behaviors are correlated to the H/E or H3/E2ratio of the films.

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A High-Performance Signal Processing System for Monopulse Tracking Radar

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.383-390.471 ◽

2011 ◽

Vol 383-390 ◽

pp. 471-475

Author(s):

Yong Bin Hong ◽

Cheng Fa Xu ◽

Mei Guo Gao ◽

Li Zhi Zhao

Keyword(s):

Signal Processing ◽

High Performance ◽

Dynamic Range ◽

Signal To Noise Ratio ◽

Processing System ◽

Digital Signal ◽

Radar Signal ◽

Signal Processing System ◽

Parallel Pipelined ◽

Tracking Radar

A radar signal processing system characterizing high instantaneous dynamic range and low system latency is designed based on a specifically developed signal processing platform. Instantaneous dynamic range loss is a critical problem when digital signal processing is performed on fixed-point FPGAs. In this paper, the problem is well resolved by increasing the wordlength according to signal-to-noise ratio (SNR) gain of the algorithms through the data path. The distinctive software structure featuring parallel pipelined processing and “data flow drive” reduces the system latency to one coherent processing interval (CPI), which significantly improves the maximum tracking angular velocity of the monopulse tracking radar. Additionally, some important electronic counter-countermeasures (ECCM) are incorporated into this signal processing system.

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Study on the Performance of the New High-Strength Steel-Encased Concrete Composite Beam (SCCB)

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.756-759.161 ◽

2013 ◽

Vol 756-759 ◽

pp. 161-165

Author(s):

Qi Yin Shi ◽

Chao Liu ◽

Li Lin Cao ◽

Zhen Wang

Keyword(s):

Cross Section ◽

High Strength Steel ◽

High Strength Concrete ◽

Composite Beam ◽

High Performance ◽

Bending Strength ◽

Theoretical Study ◽

High Strength ◽

Simply Supported ◽

Ordinary Steel

On the basis of the theoretical study and application of ordinary steel-encased concrete composite beam, this paper will focus on a new high-strength steel-encased concrete composite beam, and mainly studies high-performance steel Q420 and Q460, as well as high-strength concrete C60 and C80. Besides, an experimental study of 5 simply-supported beams is made, and the load-deflection curves of new SCCB are analyzed. The calculation formula of load which changes with depth of section and bending strength of the cross section is also analyzed. It is suggested that the calculated results announced should be identical with the experimental results.

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Highly efficient self-powered perovskite photodiode with an electron-blocking hole-transport NiOx layer

Scientific Reports ◽

10.1038/s41598-020-80640-3 ◽

2021 ◽

Vol 11 (1) ◽

Author(s):

Amir Muhammad Afzal ◽

In-Gon Bae ◽

Yushika Aggarwal ◽

Jaewoo Park ◽

Hye-Ryeon Jeong ◽

...

Keyword(s):

Energy Harvesting ◽

Bias Voltage ◽

High Performance ◽

Hole Transport ◽

Transport Layer ◽

Hole Transport Layer ◽

Zero Bias ◽

Decay Times ◽

Order Of Magnitude ◽

Self Powered

AbstractHybrid organic–inorganic perovskite materials provide noteworthy compact systems that could offer ground-breaking architectures for dynamic operations and advanced engineering in high-performance energy-harvesting optoelectronic devices. Here, we demonstrate a highly effective self-powered perovskite-based photodiode with an electron-blocking hole-transport layer (NiOx). A high value of responsivity (R = 360 mA W−1) with good detectivity (D = 2.1 × 1011 Jones) and external quantum efficiency (EQE = 76.5%) is achieved due to the excellent interface quality and suppression of the dark current at zero bias voltage owing to the NiOx layer, providing outcomes one order of magnitude higher than values currently in the literature. Meanwhile, the value of R is progressively increased to 428 mA W−1 with D = 3.6 × 1011 Jones and EQE = 77% at a bias voltage of − 1.0 V. With a diode model, we also attained a high value of the built-in potential with the NiOx layer, which is a direct signature of the improvement of the charge-selecting characteristics of the NiOx layer. We also observed fast rise and decay times of approximately 0.9 and 1.8 ms, respectively, at zero bias voltage. Hence, these astonishing results based on the perovskite active layer together with the charge-selective NiOx layer provide a platform on which to realise high-performance self-powered photodiode as well as energy-harvesting devices in the field of optoelectronics.

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Design and evaluation of a high-performance haptic interface

Robotica ◽

10.1017/s0263574700019639 ◽

1996 ◽

Vol 14 (3) ◽

pp. 321-327 ◽

Cited By ~ 86

Author(s):

R.E. Ellis ◽

O.M. Ismaeil ◽

M.G. Lipsett

Keyword(s):

High Performance ◽

Dynamic Range ◽

Evaluation Criteria ◽

Haptic Interface ◽

Human Operator ◽

Haptic Interfaces ◽

Environment Design ◽

Mechanical Constraints ◽

Computer Controlled ◽

The Many

SUMMARYA haptic interface is a computer-controlled mechanism designed to detect motion of a human operator without impeding that motion, and to feed back forces from a teleoperated robot or virtual environment. Design of such a device is not trivial, because of the many conflicting constraints the designer must face.As part of our research into haptics, we have developed a prototype planar mechanism. It has low apparent mass and damping, high structural stiffness, high force bandwidth, high force dynamic range, and an absence of mechanical singularities within its workspace. We present an analysis of the human-operator and mechanical constraints that apply to any such device, and propose methods for the evaluation of haptic interfaces. Our evaluation criteria are derived from the original task analysis, and are a first step towards a replicable methodology for comparing the performance of different devices.

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Toward High Throughput Core-CBCM CMOS Capacitive Sensors for Life Science Applications: A Novel Current-Mode for High Dynamic Range Circuitry

Sensors ◽

10.3390/s18103370 ◽

2018 ◽

Vol 18 (10) ◽

pp. 3370 ◽

Cited By ~ 2

Author(s):

Saghi Forouhi ◽

Rasoul Dehghani ◽

Ebrahim Ghafar-Zadeh

Keyword(s):

High Performance ◽

Life Science ◽

Dynamic Range ◽

Current Mode ◽

Capacitive Sensor ◽

Oxide Semiconductor ◽

Capacitance Measurement ◽

Biological Research ◽

Cmos Process ◽

Capacitive Sensors

This paper proposes a novel charge-based Complementary Metal Oxide Semiconductor (CMOS) capacitive sensor for life science applications. Charge-based capacitance measurement (CBCM) has significantly attracted the attention of researchers for the design and implementation of high-precision CMOS capacitive biosensors. A conventional core-CBCM capacitive sensor consists of a capacitance-to-voltage converter (CVC), followed by a voltage-to-digital converter. In spite of their high accuracy and low complexity, their input dynamic range (IDR) limits the advantages of core-CBCM capacitive sensors for most biological applications, including cellular monitoring. In this paper, after a brief review of core-CBCM capacitive sensors, we address this challenge by proposing a new current-mode core-CBCM design. In this design, we combine CBCM and current-controlled oscillator (CCO) structures to improve the IDR of the capacitive readout circuit. Using a 0.18 μm CMOS process, we demonstrate and discuss the Cadence simulation results to demonstrate the high performance of the proposed circuitry. Based on these results, the proposed circuit offers an IDR ranging from 873 aF to 70 fF with a resolution of about 10 aF. This CMOS capacitive sensor with such a wide IDR can be employed for monitoring cellular and molecular activities that are suitable for biological research and clinical purposes.

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Laser-Induced Growth of Titanium Nitride Microcolumns on Biased Titanium Targets

Journal of Materials Research ◽

10.1557/jmr.2005.0021 ◽

2005 ◽

Vol 20 (1) ◽

pp. 62-67 ◽

Cited By ~ 6

Author(s):

E. György ◽

A. Pérez del Pino ◽

P. Serra ◽

J.L. Morenza

Keyword(s):

Bias Voltage ◽

Single Pulse ◽

Laser Pulses ◽

High Repetition Rate ◽

Applied Bias ◽

Applied Bias Voltage ◽

Surface Microrelief ◽

High Repetition ◽

Melting Threshold ◽

Biased Samples

Titanium targets with a bias voltage ranging from −500 to +500 V were submitted to multipulse high repetition rate Nd:yttrium aluminum garnet (YAG; λ = 1.064 μm, τ ∼ 300 ns, ν = 30 kHz) laser irradiations in nitrogen at intensity values below the single-pulse melting threshold. The morphology of the TiN structures formed under the cumulative action of the laser pulses on the surface of the unbiased and biased targets was investigated by profilometry and scanning electron microscopy. Under these irradiation conditions, a specific columnar surface microrelief developed. The height of the microcolumns reached about 10–15 μm, and their diameter about 1–2 μm. The development of TiN microcolumns was enhanced by the applied bias voltage. The enhancement in the negative biased samples was stronger than that in the positive biased ones.

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Effects of Pumice-Based Porous Material on Hydration Characteristics and Persistent Shrinkage of Ultra-High Performance Concrete (UHPC)

Materials ◽

10.3390/ma12010011 ◽

2018 ◽

Vol 12 (1) ◽

pp. 11 ◽

Cited By ~ 24

Author(s):

Kaizhi Liu ◽

Rui Yu ◽

Zhonghe Shui ◽

Xiaosheng Li ◽

Xuan Ling ◽

...

Keyword(s):

High Performance ◽

High Performance Concrete ◽

Volume Fraction ◽

Energy Dispersive Spectrometer ◽

Effective Area ◽

Mineral Admixtures ◽

Ultra High Performance Concrete ◽

Composition And Structure ◽

Different Diameters ◽

Hydration Characteristics

In this paper, two kinds of pumice particles with different diameters and water absorption rates are employed to substitute the corresponding size of river sands by volume fraction, and their effects on the hydration characteristics and persistent shrinkage of Ultra-High Performance Concrete (UHPC) are investigated. The obtained experimental results show that adopting a low dosage of 0.6–1.25 mm saturated pumice as the internal curing agent in UHPC can effectively retract the persistent shrinkage deformation of concrete without a decrease of strength. Heat flow calorimetry results demonstrate that the additional water has a retarding effect and promotes the hydration process. X-ray Diffraction (XRD) and Differential Thermal Gravimetry (DTG) are utilized to quantify the Ca(OH)2 content in the hardened paste, which can confirm that the external moisture could accelerate the early cement hydration and secondary hydration of active mineral admixtures. The Ca/Si ratio of C–S–H calculated by the Energy Dispersive Spectrometer (EDS) reveals that the incorporation of wet pumice can transform the composition and structure of hydration products in its effective area.

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