scholarly journals Low-Concentration Ammonia Gas Sensors Manufactured Using the CMOS–MEMS Technique

Micromachines ◽  
2020 ◽  
Vol 11 (1) ◽  
pp. 92 ◽  
Author(s):  
Wei-Chun Shen ◽  
Po-Jen Shih ◽  
Yao-Chuan Tsai ◽  
Cheng-Chih Hsu ◽  
Ching-Liang Dai
Keyword(s):  
Complementary Metal Oxide Semiconductor ◽  
Oxide Semiconductor ◽  
Cmos Process ◽  
X Ray Diffraction ◽  
Ammonia Gas ◽  
Oxidation Reduction ◽  
Sensing Material ◽  
Voltage Signal ◽  
Cmos Mems ◽  
Good Repeatability

This study describes the fabrication of an ammonia gas sensor (AGS) using a complementary metal oxide semiconductor (CMOS)–microelectromechanical system (MEMS) technique. The structure of the AGS features interdigitated electrodes (IDEs) and a sensing material on a silicon substrate. The IDEs are the stacked aluminum layers that are made using the CMOS process. The sensing material; polypyrrole/reduced graphene oxide (PPy/RGO), is synthesized using the oxidation–reduction method; and the material is characterized using an electron spectroscope for chemical analysis (ESCA), a scanning electron microscope (SEM), and high-resolution X-ray diffraction (XRD). After the CMOS process; the AGS needs post-processing to etch an oxide layer and to deposit the sensing material. The resistance of the AGS changes when it is exposed to ammonia. A non-inverting amplifier circuit converts the resistance of the AGS into a voltage signal. The AGS operates at room temperature. Experiments show that the AGS response is 4.5% at a concentration of 1 ppm NH3; and it exhibits good repeatability. The lowest concentration that the AGS can detect is 0.1 ppm NH3

scholarly journals Research on a CMOS-MEMS Infrared Sensor with Reduced Graphene Oxide

Sensors ◽  
2020 ◽  
Vol 20 (14) ◽  
pp. 4007 ◽  
Author(s):  
Shu-Jung Chen ◽  
Bin Chen
Keyword(s):  
Graphene Oxide ◽  
Reduced Graphene Oxide ◽  
Complementary Metal Oxide Semiconductor ◽  
Oxide Semiconductor ◽  
Cmos Process ◽  
Ir Absorption ◽  
Long Distance ◽  
Ir Sensor ◽  
Reduced Graphene ◽  
Cmos Mems

In this research, a new application of reduced graphene oxide (rGO) for a complementary metal-oxide-semiconductor (CMOS)-MEMS infrared (IR) sensor and emitter is proposed. Thorough investigations of IR properties including absorption and emission were proceeded with careful calibration and measurement with a CMOS thermoelectric sensor. The thermocouples of the sensor consist of aluminum and n-polysilicon layers which are fabricated with the TSMC 0.35 μm CMOS process and MEMS post-process. In order to improve the adhesion of rGO, a sensing area at the center of the membrane is formed with an array of holes, which is easy for the drop-coating of rGO material upon the sensing region. To evaluate the performance of the IR sensor with rGO, different conditions of the IR thermal radiation experiments were arranged. The results show that the responsivity of our proposed CMOS-MEMS IR sensor with rGO increases by about 77% compared with the sensor without rGO. For different IR absorption incident angles, the measurement of field of view shows that the CMOS-MEMS IR sensor with rGO has a smaller view angle, which can be applied for the application of long-distance measuring. In addition, characteristics of the proposed thermopile are estimated and analyzed with comparisons to the available commercial sensors by the experiments.

scholarly journals A 0.35-μm CMOS-MEMS Oscillator for High-Resolution Distributed Mass Detection

Micromachines ◽  
2018 ◽  
Vol 9 (10) ◽  
pp. 484 ◽  
Author(s):  
Rafel Perelló-Roig ◽  
Jaume Verd ◽  
Joan Barceló ◽  
Sebastià Bota ◽  
Jaume Segura
Keyword(s):  
Low Cost ◽  
Electrical Characterization ◽  
Complementary Metal Oxide Semiconductor ◽  
Turnaround Time ◽  
Oxide Semiconductor ◽  
Cmos Process ◽  
Mass Detection ◽  
Electrostatically Actuated ◽  
Resonator Structure ◽  
Cmos Mems

This paper presents the design, fabrication, and electrical characterization of an electrostatically actuated and capacitive sensed 2-MHz plate resonator structure that exhibits a predicted mass sensitivity of ~250 pg·cm−2·Hz−1. The resonator is embedded in a fully on-chip Pierce oscillator scheme, thus obtaining a quasi-digital output sensor with a short-term frequency stability of 1.2 Hz (0.63 ppm) in air conditions, corresponding to an equivalent mass noise floor as low as 300 pg·cm−2. The monolithic CMOS-MEMS sensor device is fabricated using a commercial 0.35-μm 2-poly-4-metal complementary metal-oxide-semiconductor (CMOS) process, thus featuring low cost, batch production, fast turnaround time, and an easy platform for prototyping distributed mass sensors with unprecedented mass resolution for this kind of devices.

scholarly journals Phase Change Metasurfaces by Continuous or Quasi-Continuous Atoms for Active Optoelectronic Integration

Materials ◽  
2021 ◽  
Vol 14 (5) ◽  
pp. 1272
Author(s):  
Zhihua Fan ◽  
Qinling Deng ◽  
Xiaoyu Ma ◽  
Shaolin Zhou
Keyword(s):  
Phase Change ◽  
Phase Change Materials ◽  
Complementary Metal Oxide Semiconductor ◽  
Photonic Devices ◽  
Oxide Semiconductor ◽  
Cmos Process ◽  
Nanophotonic Devices ◽  
Optoelectronic Integration ◽  
Hybrid Devices ◽  
Micro Electromechanical System

In recent decades, metasurfaces have emerged as an exotic and appealing group of nanophotonic devices for versatile wave regulation with deep subwavelength thickness facilitating compact integration. However, the ability to dynamically control the wave–matter interaction with external stimulus is highly desirable especially in such scenarios as integrated photonics and optoelectronics, since their performance in amplitude and phase control settle down once manufactured. Currently, available routes to construct active photonic devices include micro-electromechanical system (MEMS), semiconductors, liquid crystal, and phase change materials (PCMs)-integrated hybrid devices, etc. For the sake of compact integration and good compatibility with the mainstream complementary metal oxide semiconductor (CMOS) process for nanofabrication and device integration, the PCMs-based scheme stands out as a viable and promising candidate. Therefore, this review focuses on recent progresses on phase change metasurfaces with dynamic wave control (amplitude and phase or wavefront), and especially outlines those with continuous or quasi-continuous atoms in favor of optoelectronic integration.

scholarly journals Universal Filter Based on Compact CMOS Structure of VDDDA

Sensors ◽  
2021 ◽  
Vol 21 (5) ◽  
pp. 1683
Author(s):  
Winai Jaikla ◽  
Fabian Khateb ◽  
Tomasz Kulej ◽  
Koson Pitaksuttayaprot
Keyword(s):  
Metal Oxide ◽  
Dynamic Range ◽  
Complementary Metal Oxide Semiconductor ◽  
Metal Oxide Semiconductor ◽  
Experimental Results ◽  
Oxide Semiconductor ◽  
Cmos Process ◽  
Voltage Gain ◽  
Universal Filter ◽  
Mos Transistor

This paper proposes the simulated and experimental results of a universal filter using the voltage differencing differential difference amplifier (VDDDA). Unlike the previous complementary metal oxide semiconductor (CMOS) structures of VDDDA that is present in the literature, the present one is compact and simple, owing to the employment of the multiple-input metal oxide semiconductor (MOS) transistor technique. The presented filter employs two VDDDAs, one resistor and two grounded capacitors, and it offers low-pass: LP, band-pass: BP, band-reject: BR, high-pass: HP and all-pass: AP responses with a unity passband voltage gain. The proposed universal voltage mode filter has high input impedances and low output impedance. The natural frequency and bandwidth are orthogonally controlled by using separated transconductance without affecting the passband voltage gain. For a BP filter, the root mean square (RMS) of the equivalent output noise is 46 µV, and the third intermodulation distortion (IMD3) is −49.5 dB for an input signal with a peak-to peak of 600 mV, which results in a dynamic range (DR) of 73.2 dB. The filter was designed and simulated in the Cadence environment using a 0.18-µm CMOS process from Taiwan semiconductor manufacturing company (TSMC). In addition, the experimental results were obtained by using the available commercial components LM13700 and AD830. The simulation results are in agreement with the experimental one that confirmed the advantages of the filter.

Millimeter-wave dual-mode and dual-band switchable Gilbert up-conversion mixer in 65-nm CMOS process

2021 ◽  
pp. 1-5
Author(s):  
Fang Zhu ◽  
Guo Qing Luo
Keyword(s):  
Millimeter Wave ◽  
Complementary Metal Oxide Semiconductor ◽  
Local Oscillator ◽  
Metal Oxide Semiconductor ◽  
Oxide Semiconductor ◽  
Dual Band ◽  
Cmos Process ◽  
Pumping Power ◽  
Dual Mode ◽  
Dc Power

Abstract In this paper, a millimeter-wave (MMW) dual-mode and dual-band switchable Gilbert up-conversion mixer in a commercial 65-nm complementary metal oxide semiconductor (CMOS) process is presented. By simply changing the bias, the proposed CMOS Gilbert up-conversion mixer can be switched between subharmonic and fundamental operation modes for MMW dual-band applications. With a low local oscillator pumping power of 3 dBm and low dc power consumption of 6 mW, the proposed CMOS Gilbert up-conversion mixer exhibits a measured conversion gain of −0.5 ± 1.5 dB from 37 to 50 GHz and 2.5 ± 1.5 dB from 17.5 to 32 GHz for the subharmonic and fundamental modes, respectively.

scholarly journals Performance Comparison of Carry-Lookahead and Carry-Select Adders Based on Accurate and Approximate Additions

Electronics ◽  
2018 ◽  
Vol 7 (12) ◽  
pp. 369 ◽  
Author(s):  
Padmanabhan Balasubramanian ◽  
Nikos Mastorakis
Keyword(s):  
High Speed ◽  
Digital Signal ◽  
Complementary Metal Oxide Semiconductor ◽  
Performance Comparison ◽  
Oxide Semiconductor ◽  
Cmos Process ◽  
Least Significant Bit ◽  
Design Metrics ◽  
Ripple Carry Adder ◽  
Speed Performance

Addition is a fundamental operation in microprocessing and digital signal processing hardware, which is physically realized using an adder. The carry-lookahead adder (CLA) and the carry-select adder (CSLA) are two popular high-speed, low-power adder architectures. The speed performance of a CLA architecture can be improved by adopting a hybrid CLA architecture which employs a small-size ripple-carry adder (RCA) to replace a sub-CLA in the least significant bit positions. On the other hand, the power dissipation of a CSLA employing full adders and 2:1 multiplexers can be reduced by utilizing binary-to-excess-1 code (BEC) converters. In the literature, the designs of many CLAs and CSLAs were described separately. It would be useful to have a direct comparison of their performances based on the design metrics. Hence, we implemented homogeneous and hybrid CLAs, and CSLAs with and without the BEC converters by considering 32-bit accurate and approximate additions to facilitate a comparison. For the gate-level implementations, we considered a 32/28 nm complementary metal-oxide-semiconductor (CMOS) process targeting a typical-case process–voltage–temperature (PVT) specification. The results show that the hybrid CLA/RCA architecture is preferable among the CLA and CSLA architectures from the speed and power perspectives to perform accurate and approximate additions.

Review: Static and Dynamic Analysis Methods for Multi-Branch Biasing Circuits

2018 ◽  
Vol 27 (13) ◽  
pp. 1830008
Author(s):  
Jin Wu ◽  
Pengfei Dai ◽  
Jie Peng ◽  
Lixia Zheng ◽  
Weifeng Sun
Keyword(s):  
Feedback Loop ◽  
Supply Voltage ◽  
Complementary Metal Oxide Semiconductor ◽  
Oxide Semiconductor ◽  
Critical Parameters ◽  
Cmos Process ◽  
Stable Equilibrium Point ◽  
Static And Dynamic Analysis ◽  
Text Structures ◽  
Different Types

The fundamental theories and primary structures for the multi-branch self-biasing circuits are reviewed in this paper. First, the [Formula: see text]/[Formula: see text] and [Formula: see text]/[Formula: see text] structures illustrating the static current definition mechanism are presented, including the conditions of starting up and entering into a stable equilibrium point. Then, the AC method based on the loop gain evaluation is utilized to analyze different types of circuits. On this basis, the laws which can couple the branches of self-biasing circuits to construct a suitable close feedback loop are summarized. By adopting Taiwan Semiconductor Manufacturing Company (TSMC)’s 0.18[Formula: see text][Formula: see text]m complementary metal–oxide–semiconductor (CMOS) process with 1.8[Formula: see text][Formula: see text] supply voltage, nearly all the circuits mentioned in the paper are simulated in the same branch current condition, which is close to the corresponding calculated results. Therefore, the methods summarized in this paper can be utilized for distinguishing, constructing, and optimizing critical parameters for various structures of the self-biasing circuits.

scholarly journals A Regulated Temperature-Insensitive High-Voltage Charge Pump in Standard CMOS Process for Micromachined Gyroscopes

Sensors ◽  
2019 ◽  
Vol 19 (19) ◽  
pp. 4149
Author(s):  
Xiang Li ◽  
Rui Li ◽  
Chunge Ju ◽  
Bo Hou ◽  
Qi Wei ◽  
...  
Keyword(s):  
Metal Oxide ◽  
High Voltage ◽  
Output Voltage ◽  
Charge Pump ◽  
Complementary Metal Oxide Semiconductor ◽  
Metal Oxide Semiconductor ◽  
Oxide Semiconductor ◽  
Cmos Process ◽  
Temperature Changes ◽  
Adjustable Range

Micromachined gyroscopes require high voltage (HV) for actuation and detection to improve its precision, but the deviation of the HV caused by temperature fluctuations will degrade the sensor’s performance. In this paper, a high-voltage temperature-insensitive charge pump is proposed. Without adopting BCD (bipolar-CMOS-DMOS) technology, the output voltage can be boosted over the breakdown voltage of n-well/substrate diode using triple-well NMOS (n-type metal-oxide-semiconductor) transistors. By controlling the pumping clock’s amplitude continuously, closed-loop regulation is realized to reduce the output voltage’s sensitivity to temperature changes. Besides, the output level is programmable linearly in a large range by changing the reference voltage. The whole circuit has been fabricated in a 0.18- μ m standard CMOS (complementary metal-oxide-semiconductor) process with a total area of 2.53 mm 2 . Measurements indicate that its output voltage has a linear adjustable range from around 13 V to 16.95 V, and temperature tests show that the maximum variations of the output voltage at − 40 ∼ 80 ∘ C are less than 1.1%.

scholarly journals Portable Real-Time Detection of Pb(II) Using a CMOS MEMS-Based Nanomechanical Sensing Array Modified with PEDOT:PSS

Nanomaterials ◽  
2020 ◽  
Vol 10 (12) ◽  
pp. 2454
Author(s):  
Yi-Kuang Yen ◽  
Chao-Yu Lai
Keyword(s):  
Limit Of Detection ◽  
Quality Measurement ◽  
Complementary Metal Oxide Semiconductor ◽  
Cost Effective ◽  
Sample Volume ◽  
Small Sample ◽  
Oxide Semiconductor ◽  
Resistance Change ◽  
Site Water ◽  
Cmos Mems

Detecting the concentration of Pb2+ ions is important for monitoring the quality of water due to it can become a health threat as being in certain level. In this study, we report a nanomechanical Pb2+ sensor by employing the complementary metal-oxide-semiconductor microelectromechanical system (CMOS MEMS)-based piezoresistive microcantilevers coated with PEDOT:PSS sensing layers. Upon reaction with Pb2+, the PEDOT:PSS layer was oxidized which induced the surface stress change resulted in a subsequent bending of the microcantilever with the signal response of relative resistance change. This sensing platform has the advantages of being mass-produced, miniaturized, and portable. The sensor exhibited its sensitivity to Pb2+ concentrations in a linear range of 0.01–1000 ppm, and the limit of detection was 5 ppb. Moreover, the sensor showed the specificity to Pb2+, required a small sample volume and was easy to operate. Therefore, the proposed analytical method described here may be a sensitive, cost-effective and portable sensing tool for on-site water quality measurement and pollution detection.

scholarly journals Characterization of dislocations in germanium layers grown on (011)- and (111)-oriented silicon by coplanar and noncoplanar X-ray diffraction

2015 ◽  
Vol 48 (3) ◽  
pp. 655-665 ◽  
Author(s):  
Andrei Benediktovitch ◽  
Alexei Zhylik ◽  
Tatjana Ulyanenkova ◽  
Maksym Myronov ◽  
Alex Ulyanenkov
Keyword(s):  
Dislocation Line ◽  
Complementary Metal Oxide Semiconductor ◽  
Metal Oxide Semiconductor ◽  
Oxide Semiconductor ◽  
Misfit Dislocations ◽  
X Ray Diffraction ◽  
X Ray ◽  
Lattice Constants ◽  
Silicon And Germanium

Strained germanium grown on silicon with nonstandard surface orientations like (011) or (111) is a promising material for various semiconductor applications, for example complementary metal-oxide semiconductor transistors. However, because of the large mismatch between the lattice constants of silicon and germanium, the growth of such systems is challenged by nucleation and propagation of threading and misfit dislocations that degrade the electrical properties. To analyze the dislocation microstructure of Ge films on Si(011) and Si(111), a set of reciprocal space maps and profiles measured in noncoplanar geometry was collected. To process the data, the approach proposed by Kaganer, Köhler, Schmidbauer, Opitz & Jenichen [Phys. Rev. B, (1997),55, 1793–1810] has been generalized to an arbitrary surface orientation, arbitrary dislocation line direction and noncoplanar measurement scheme.

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