An acceleration sensor is an essential component of the vibration measurement, while the passivity and sensitivity are the pivotal features for its application. Here, we report a self-powered and highly sensitive acceleration sensor based on a triboelectric nanogenerator composed of a liquid metal mercury droplet (LMMD) and nanofiber-networked polyvinylidene fluoride (nn-PVDF) film. Due to the ultrahigh surface-to-volume ratio of nn-PVDF film and high surface tension, high mass density, high elastic as well as mechanical robustness of LMMD, the open-circuit voltage and short-circuit current reach up to 15.5 V and 300 nA at the acceleration of 60 m/s2, respectively. The acceleration sensor has a wide detection range from 0 to 60 m/s2 with a high sensitivity of 0.26 V·s/m2. Also, the output voltage and current show a negligible decrease over 200,000 cycles, evidently presenting excellent stability. Moreover, a high-speed camera was employed to dynamically capture the motion state of the acceleration sensor ...

Self-Powered Acceleration Sensor Based on Liquid Metal Triboelectric Nanogenerator for Vibration Monitoring

All-in-one 3D acceleration sensor based on coded liquid–metal triboelectric nanogenerator for vehicle restraint system

A kind of cutting force sensor based on semi-conductive strain gauge is proposed in this paper in order to optimize the contradiction between sensitivity and natural frequency of strain-gauge type sensors. A new sensing element of two mutual-perpendicular octagonal rings1 (TMPOR) is developed to improve natural frequency; and semi-conductive strain gauge that fabricated by MEMS (micro-electro-mechanical system) technique is used to enhance sensitivity of the sensor due to its higher gauge factor (GF). Static calibration experiment results show that semi-conductive strain gauge has improved the sensitivity by 16 times than traditional metal foil strain gauge, which proves the feasibility of settling the contradiction aforementioned by using MEMS technique. Modal impact test indicates that the natural frequency of the fabricated sensor is 771 Hz in primary direction, which fulfills its most application in high speed machining process. During dynamic cutting force measurement test, the developed sensor exhibits satisfying ability in dynamic cutting force signal detection. Generally, the MEMS technique based sensor shows great potential in solving technical defect between sensitivity and natural frequency in current cutting force sensor research.

Design and development of a cutting force sensor based on semi-conductive strain gauge

This paper reports the development of a microaccelerometer with high performance in linearity and cross-axis sensitivity. The accelerometer consisted of a vertical, double-ended flexural beam, a proof mass integrated at the middle section of the beam, and four suspended piezoresistors fixed at the mass block and across the trenches to the anchor pads. The mass block had maximum displacements of the dynamic structure which would activate the sensors to deliver maximal output. The sensing chip was fabricated on a silicon-on-insulator wafer through MEMS processes. The accelerometer was placed on a rate table that provided stable centrifugal acceleration up to approximately 3000 ×  G for testing. The output voltage of the accelerometer was digitized and radio-frequency transmitted for remote data acquisition. The correlations for the individual runs showed that the accelerometer had a sensitivity of 3.0015 μV/ V exc / G with extraordinary performance. The linearity of the sensing output was only 0.11% of full scale output (FS, or 59 dB), as deduced from the average standard deviation of all test runs. The average of the maximum reading deviations from the corresponding correlated curves was approximately 0.26% FS. Moreover, the cross-axis sensitivity for the two orthogonal directions nearly vanished in the test range. With the high rigidity of the microstructure, the accelerometer exhibited an ultra high performance factor of 25.8 × 10 6  MHz 2 . The accelerometer possessed exceptional sensitivity, linearity, and repeatability, and extremely low cross-axis interference and noise.

Vertical-plate-type microaccelerometer with high linearity and low cross-axis sensitivity

Ultralight graphene elastomer-based flexible sensors are developed to detect subtle vibrations within a broad frequency range. The same device can be employed as an accelerometer, tested within the experimental bandwidth of 20–300 Hz as well as a microphone, monitoring sound pressures from 300 to 20 000 Hz. The sensing element does not contain any metal parts, making them undetectable by external sources and can provide an acceleration sensitivity of 2.6 mV/g, which is higher than or comparable to those of rigid Si-based piezoresistive microelectromechanical systems (MEMS).

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Detecting Subtle Vibrations Using Graphene-Based Cellular Elastomers

System development and characterization of a low noise low offset SOI MEMS–CMOS PCB-integrated multi-chip ±4g piezoresistive accelerometer sensor comprising a coupled multi-bandwidth variable-gain amplifier block and a thermal sensitivity and offset compensation block is presented in this work. Custom design and fabrication has been carried out for both the SOI MEMS sensor and the analog front-end for high precision and operational reliability. The system is shown to have a scale factor of ∼4 mV/g and an output nonlinearity

A high precision SOI MEMS–CMOS ±4g piezoresistive accelerometer

BSIM6 is the new Compact Model Coalition (CMC) standard bulk MOSFET model. It offers excellent fitting capability, accurate RF/analog simulations, and similar implementation features of the small dimension effects as included in the popular BSIM4 model. These features make BSIM6 a very desirable candidate for future nano-MOSFET simulations. In this work we evaluate the capabilities of the model and perform benchmark tests to assess the strengths of the model. Bulk 90nm technology MOSFET data is used to extract BSIM6 for analog/RF specific applications. Industry standard benchmark tests have been performed and results shown against the hardware data (where applicable). The model is found to correlate very well with hardware data and passes all important model quality benchmark tests for analog/RF applications.

BSIM6 -- Benchmarking the Next-Generation MOSFET Model for RF Applications

In this paper we present a model to capture the effect of the body-bias on the overlap capacitances. The main hurdle while introducing body-bias dependence in gate-source and gate-drain overlap capacitances is maintaining reciprocity for all capacitances. We propose a subcircuit approach to help maintain reciprocity while including body-bias dependence in overlap charges. The approach is generic, and works for any device. The model has been implemented in BSIM6 industry standard model and has been validated with TCAD simulations as well as experimental measurements.

Modeling of Body-Bias Dependence of Overlap Capacitances in Bulk MOSFETs

A 6 GHz CMOS low-noise amplifier (LNA) with very low noise-figure (NF) of 092 dB is reported in this paper An inductively degenerated cascode topology is used for the LNA The common source device is a floating body transistor for higher unity gain cut-off frequency and lower NFmin while the common gate device is a body contacted device with higher self gain High resistivity (HR) silicon-on-insulator (SOI) technology renders higher quality factor (Q) values for inductors which results in reduced NF The prototype LNA is fabricated (Fig 1) and characterized using a 180 nm RF-SOI CMOS technology Measurements show 159 dB of gain, 092 dB of NF, -11 dBm of input third-order intercept point (IIP3) for the LNA, with 12 mW dc power consumption

A 6 GHz 0.92 dB NF Cascode LNA in 180 nm SOI CMOS Technology

In this paper, significant improvement in cascode LNA performance is demonstrated by using a new high self gain (HSG) common gate (CG) transistor. Emphasis has been on making the output conductance $g_{ds}$ lower and flatter with drain bias. A prototype cascode LNA is designed and fabricated using the developed HSG device in state-of-the-art 0.13 RF SOI technology. Thanks to the HSG device, more than +5 dBm input inter-modulation product (IIP3) improvement is seen in measurements. Very high gain of 19.5 dB at 2.5 GHz with IIP3 value of +1.5 dBm are seen in measurements. Due to optimized transistor sizing, the designed LNA operates at low power of 6.25 mW where 5.2 mA of current is drawn from 1.2 V supply. With integrated high quality factor inductors on high resistivity SOI substrate, the LNA also demonstrates very low noise figure of 0.85 dB. Furthermore, excellent correlation between model simulations and measurements is demonstrated.

Anupam Dutta

Papers

A high precision SOI MEMS–CMOS ±4g piezoresistive accelerometer

BSIM6 -- Benchmarking the Next-Generation MOSFET Model for RF Applications

Modeling of Body-Bias Dependence of Overlap Capacitances in Bulk MOSFETs

A 6 GHz 0.92 dB NF Cascode LNA in 180 nm SOI CMOS Technology

A 6.25 mW, +21 dBm OIP3, 0.85 dB NF, 2.5 GHz LNA Employing High Self Gain Device in $0.13 \mu \mathrm{m}$ SOI Technology