This paper presents the design, fabrication, and preliminary experimental result of an electric field microsensor based on the structure of piezoelectric interdigitated cantilevers with staggered vertical vibration mo...This paper presents the design, fabrication, and preliminary experimental result of an electric field microsensor based on the structure of piezoelectric interdigitated cantilevers with staggered vertical vibration mode. The working principle of this electric field microsensor is demonstrated, and the induced charges and structural parameters of this microsensor are simulated by the finite element method. The electric field microsensor was fabricated by Micro-Electro Mechanical Systems(MEMS) technique. Each cantilever is a multilayer compound structure(Al/Si3N4/ Pt/PZT/Pt/ Ti/SiO 2/Si), and Piezoelectric, PieZ oelectric ceramic Transducer(PZT)(PbZ rxTi(1–x)O3) layer, prepared by sol-gel method, is used as the piezoelectric material to drive the cantilevers vibrating. This electric field microsensor was tested under the DC electric field with the field intensity from 0 to 5×104 V/m. The output voltage signal of the electric field microsensor has a good linear relationship to the intensity of applied electric field. The performance could be improved with the optimized design of structure, and reformative fabrication processes of PZT material.展开更多
Sulfate reducing bacteria（SRB） play significant roles in anaerobic environments in oil sands mature fine tailings（MFTs）. Hydrogen sulfide（H2S） is produced during the biological sulfate reduction process. The pro...Sulfate reducing bacteria（SRB） play significant roles in anaerobic environments in oil sands mature fine tailings（MFTs）. Hydrogen sulfide（H2S） is produced during the biological sulfate reduction process. The production of toxic H2S is one of the concerns because it may hinder the landscape remediation efficiency of oil sands tailing ponds. In present study, the in situ activity and the community structure of SRB in MFT and gypsum amended MFT in two settling columns were investigated. Combined techniques of H2S microsensor and dissimilatory sulfite reductase β-subunit（dsrB） genes-based real time quantitative polymerase chain reaction（qPCR） were applied to detect the in situ H2S and the abundance of SRB. A higher diversity of SRB and more H2S were observed in gypsum amended MFT than that in MFT, indicating a higher sulfate reduction activity in gypsum amended MFT; in addition, the activity of SRB varied as depth in both MFT and gypsum amended MFT： the deeper the more H2S produced. Long-term plans for tailings management can be assessed more wisely with the information provided in this study.展开更多
A novel portable instrument developed for field determinations of complex mixtures of volatile organic compounds (VOCs) is described.The key features of the instrument are a miniature multi-stage adsorbent preconcentr...A novel portable instrument developed for field determinations of complex mixtures of volatile organic compounds (VOCs) is described.The key features of the instrument are a miniature multi-stage adsorbent preconcentrator/focuser,two series-coupled separation columns with pressure and temperature tunable retention control,and an integrated array of four chemiresistor (CR) sensors coated with Au-thiolate monolayer-protected nanoparticles (MPN).MPN-CR array response patterns are used with retention times to identify eluting vapors.Air is used as the carrier gas.Calibrations of 20 common indoor air contaminants gave LODs in the range of 0.05 ng/g～0.53 ng/g for a 1 L sample volume.Results of preliminary analyses of characteristic VOCs generated from U.S.currency as well as vapor-phase markers of environmental tobacco smoke (ETS) at low-or sub-ng/g levels are presented.展开更多
A high performance CMOS band-gap voltage reference circuit that can be used in interface integrated circuit of microsensor and compatible with 0. 6 μm ( double poly) mix process is proposed in this paper. The circuit...A high performance CMOS band-gap voltage reference circuit that can be used in interface integrated circuit of microsensor and compatible with 0. 6 μm ( double poly) mix process is proposed in this paper. The circuit can be employed in the range of 1. 8 - 8 V and carry out the first-order PTAT ( proportional to absolute temperature) temperature compensation. Through using a two-stage op-amp with a NMOS input pair as a negative feedback op-amp,the PSRR ( power supply rejection ratio) of the entire circuit is increased,and the temperature coefficient of reference voltage is decreased. Results from HSPICE simulation show that the PSRR is - 72. 76 dB in the condition of low-frequency,the temperature coefficient is 2. 4 × 10 -6 in the temperature range from - 10 ℃ to 90 ℃ and the power dissipation is only 14 μW when the supply voltage is 1. 8 V.展开更多
The purpose of this paper is to study the magnetomechanicalcharacteristic of a microsensor which is composed of a cantileveredbeam-plate with ferromagnetic films in order to measure the magneticfield from the deformat...The purpose of this paper is to study the magnetomechanicalcharacteristic of a microsensor which is composed of a cantileveredbeam-plate with ferromagnetic films in order to measure the magneticfield from the deformation of plate when the microsensor is locatedin the magnetic field. To this end, a nu- merical approach made up ofthe finite element method for magnetic field and the finitedifference method for deflection of the microsensor is proposed toperform the numerical analysis of deflection under magnetoelasticinteraction. Some quantitative results of a case study for themagnetoelastic characteristic between the mag- netic field anddeflection of the microsensor in the magnetic field are given. Theresults show that this mi- crosensor can be used not only to measurethe magnitude of magnetic intensity, but also to possibly monitor thedirection of the vector of the magnetic field.展开更多
To address the need for the on-site measurement of aging oil, in this paper, we propose an impedance-based microsensor for analyzing the moisture content in engine oil. Using a microfabrication process, we fabricated ...To address the need for the on-site measurement of aging oil, in this paper, we propose an impedance-based microsensor for analyzing the moisture content in engine oil. Using a microfabrication process, we fabricated an interdigitated microelectrode and integrated it with a 3 D-printed microcontainer to produce a microsensor that can detect changes in the permittivity of oil. When the moisture content in oil increases, this sensor can detect the resulting change in the oil impedance, which is related to its permittivity, and then determine the degree to which the oil has aged. The test results show that the proposed microsensor has the advantages of being small and having high sensitivity, good accuracy, and the ability to be combined with hand-held instruments.The proposed method is expected to be used for the rapid, low cost, on-site determination of oil aging.展开更多
Dihydronicotinamide adenine dinucleotide(NADH)is an important enzyme in all living cells,which is found to be abnormally expressed in cancer cells.Since it is redox-active,an electrochemical detection method would be ...Dihydronicotinamide adenine dinucleotide(NADH)is an important enzyme in all living cells,which is found to be abnormally expressed in cancer cells.Since it is redox-active,an electrochemical detection method would be suitable for monitoring its concentration in biological fluids.Here we present a strategy for specific determination of NADH in real human serum by using RhIr@MoS2 nanohybrids based microsensor.To implement the protocol,RhIr nanocrysrals are in-situ grown onto MoS2 interlayers forming a nanohybrid structure(RhIr@MoS2).After being locally deposited on an electrochemical microsensor,it could be used for the analysis of NADH.The developed RhIr@MoS2 nanohybrids based microsensor possesses the ability for analyzing NADH at the applied potential of 0.07 V(much lower than most reported values).The detection limit is evaluated as low as 1 nmol/L even in bovine serum albumin(BSA)media.In addition,the sampling analysis of human serum from cancer patients and health controls shows that the microsensor displays good diagnostic sensitivity and specificity,illustrating that this developed detection technique is a relatively accurate method for measuring NADH in biological fluids.The proposed electrochemical microsensor assay also owns the benefits of convenience,disposable and easy processing,which make it a great possibility for future point-of-care cancer diagnosis.展开更多
In vivo monitoring of animal physiological information plays a crucial role in promptly alerting humans to potential diseases in animals and aiding in the exploration of mechanisms underlying human diseases.Currently,...In vivo monitoring of animal physiological information plays a crucial role in promptly alerting humans to potential diseases in animals and aiding in the exploration of mechanisms underlying human diseases.Currently,implantable electrochemical microsensors have emerged as a prominent area of research.These microsensors not only fulfill the technical requirements for monitoring animal physiological information but also offer an ideal platform for integration.They have been extensively studied for their ability to monitor animal physiological information in a minimally invasive manner,characterized by their bloodless,painless features,and exceptional performance.The development of implantable electrochemical microsensors for in vivo monitoring of animal physiological information has witnessed significant scientific and technological advancements through dedicated efforts.This review commenced with a comprehensive discussion of the construction of microsensors,including the materials utilized and the methods employed for fabrication.Following this,we proceeded to explore the various implantation technologies employed for electrochemical microsensors.In addition,a comprehensive overview was provided of the various applications of implantable electrochemical microsensors,specifically in the monitoring of diseases and the investigation of disease mechanisms.Lastly,a concise conclusion was conducted on the recent advancements and significant obstacles pertaining to the practical implementation of implantable electrochemical microsensors.展开更多
In modern complex systems,real-time regression prediction plays a vital role in performance evaluation and risk warning.Nevertheless,existing methods still face challenges in maintaining stability and predictive accur...In modern complex systems,real-time regression prediction plays a vital role in performance evaluation and risk warning.Nevertheless,existing methods still face challenges in maintaining stability and predictive accuracy under complex conditions.To address these limitations,this study proposes an online prediction approach that integrates event tracking sensitivity analysis with machine learning.Specifically,a real-time event tracking sensitivity analysis method is employed to capture and quantify the impact of key events on system outputs.On this basis,a mutualinformation–based self-extraction mechanism is introduced to construct prior weights,which are then incorporated into a LightGBM prediction model.Furthermore,iterative optimization of the feature selection threshold is performed to enhance both stability and accuracy.Experiments on composite microsensor data demonstrate that the proposed method achieves robust and efficient real-time prediction,with potential extension to industrial monitoring and control applications.展开更多
Meeting the growing demands for accuracy,resolution and response time of high-pressure microsensors applicated in ocean science and petroleum industry,this paper developed a silicon resonant high pressure microsensor ...Meeting the growing demands for accuracy,resolution and response time of high-pressure microsensors applicated in ocean science and petroleum industry,this paper developed a silicon resonant high pressure microsensor based on volume compressed sensing with dual resonators supported by micro beams.In operation,the frequency of resonators shifts while the volume of microsensor compressed under high pressure.A couple of micro beams were introduced to support resonators and protect resonators from buckling in high pressure.At the meanwhile,the theoretical model of micro beams was established.Based on the expression between geometric parameters of micro beams and pressure sensitivity of resonators,the micro beams of the two resonators were modified that results in different pressure sensitivities of two resonators,which effectively performed temperature self-compensation.An eutectic bonding is adopted for wafer vacuum packaged.Dealing with potentially complex hydraulic measurement,the microsensors were surrounded by silicone oil and sealed with a corrugated diaphragm and a base.The pressure sensitivities of fabricated microsensors were quantified as 0.003 kHz/MPa(~30 ppm/MPa)of Resonator Ⅰ and−0.118 kHz/MPa(~−1311 ppm/MPa)of Resonator Ⅱ under 20℃,which match with theoretical analysis.Finally,the accuracy of this microsensors is better than 0.01%FS with temperature self-compensation under the pressure range of 0.1~70 MPa from−10℃to 50℃,along with a response time better than 10 ms and a resolution of 100 Pa.This paper provided an effective structure of micro beams for resonant high-pressure microsensors combined with volume compressed sensing,derived the quantitative relationship between key structural parameters and sensitivity,and performed a possibility of high accuracy and high resolution measurements of a much wider pressure range.展开更多
This paper presents a single-chip 3D electric field microsensor, in which a sensing element is set at the center to detect the Z-axis component of an electrostatic field. Two pairs of sensing elements with the same st...This paper presents a single-chip 3D electric field microsensor, in which a sensing element is set at the center to detect the Z-axis component of an electrostatic field. Two pairs of sensing elements with the same structure are arranged in a cross-like configuration to measure the X- and Y-axis electrostatic field components. An in-plane rotary mechanism is used in the microsensor to detect the X-, Y-, and Z-axis electrostatic field components simultaneously. The proposed microsensor is compact and presents high integration. The microsensor is fabricated through a MetalMUMPS process. Experimental results show that in the range of 0-50 kV/m, the linearity errors of the microsensor are within 5.5%, and the total measure- ment errors of the three electrostatic field components are less than 14.04%.展开更多
A novel low-pass filter that consists of a switched capacitor filter （SCF） and its antialiasing prefilter and smoothing postfilter is proposed for a microsensor signal processing system, which is used in separation ...A novel low-pass filter that consists of a switched capacitor filter （SCF） and its antialiasing prefilter and smoothing postfilter is proposed for a microsensor signal processing system, which is used in separation point detection on the surface of micro air vehicles. In the system, the filter is not only applied to finish the function of filtering but also used as the front end antialiasing filter of the over sampling analog-to-digital converter. This proposed implementation mostly relies on the design of a high-precision SCF employing a correlated double sampling technique and optimisation switches. Simultaneously, the multiple-loop feedback low pass filter with good high frequency attenuation characteristics is applied as the pre- and postfilter. The design is implemented in the Central Semiconductor Manufacturing Corporation （CSMC） 0.5 μm double-poly three-metal （2P3M） 3 chip die area occupies only 0.39 mm2 and dissipatesl.53 mW. 3 V CMOS technology, with satisfactory results, The展开更多
This paper presents a high precision CMOS opamp suitable for ISFET readout. The opamp is tailored to provide a constant bias condition for ISFET as part of the readout circuits and,hence,is compatible for single chip ...This paper presents a high precision CMOS opamp suitable for ISFET readout. The opamp is tailored to provide a constant bias condition for ISFET as part of the readout circuits and,hence,is compatible for single chip integration with the sensor. A continuous time auto-zero stabilization technique is studied and employed, with the aim of suppressing the low frequency noises, including the offset voltage, 1/f noise, and temperature drift. The design is based on a 0.35μm CMOS process. With a 3.3V power supply,it maintains a DC open loop gain of more than 100dB and an offset voltage of around 11μV,while the overall power dissipation is only 1.48mW. With this opamp, a pH microsensor is constructed, of which the functionality is verified by experimental tests.展开更多
文摘This paper presents the design, fabrication, and preliminary experimental result of an electric field microsensor based on the structure of piezoelectric interdigitated cantilevers with staggered vertical vibration mode. The working principle of this electric field microsensor is demonstrated, and the induced charges and structural parameters of this microsensor are simulated by the finite element method. The electric field microsensor was fabricated by Micro-Electro Mechanical Systems(MEMS) technique. Each cantilever is a multilayer compound structure(Al/Si3N4/ Pt/PZT/Pt/ Ti/SiO 2/Si), and Piezoelectric, PieZ oelectric ceramic Transducer(PZT)(PbZ rxTi(1–x)O3) layer, prepared by sol-gel method, is used as the piezoelectric material to drive the cantilevers vibrating. This electric field microsensor was tested under the DC electric field with the field intensity from 0 to 5×104 V/m. The output voltage signal of the electric field microsensor has a good linear relationship to the intensity of applied electric field. The performance could be improved with the optimized design of structure, and reformative fabrication processes of PZT material.
基金financial supports from Natural Sciences and Engineering Research Council (NSERC) of CanadaCanadian School of Energy and the Environment (CSEE)China Scholarship Council (CSC)
文摘Sulfate reducing bacteria（SRB） play significant roles in anaerobic environments in oil sands mature fine tailings（MFTs）. Hydrogen sulfide（H2S） is produced during the biological sulfate reduction process. The production of toxic H2S is one of the concerns because it may hinder the landscape remediation efficiency of oil sands tailing ponds. In present study, the in situ activity and the community structure of SRB in MFT and gypsum amended MFT in two settling columns were investigated. Combined techniques of H2S microsensor and dissimilatory sulfite reductase β-subunit（dsrB） genes-based real time quantitative polymerase chain reaction（qPCR） were applied to detect the in situ H2S and the abundance of SRB. A higher diversity of SRB and more H2S were observed in gypsum amended MFT than that in MFT, indicating a higher sulfate reduction activity in gypsum amended MFT; in addition, the activity of SRB varied as depth in both MFT and gypsum amended MFT： the deeper the more H2S produced. Long-term plans for tailings management can be assessed more wisely with the information provided in this study.
文摘A novel portable instrument developed for field determinations of complex mixtures of volatile organic compounds (VOCs) is described.The key features of the instrument are a miniature multi-stage adsorbent preconcentrator/focuser,two series-coupled separation columns with pressure and temperature tunable retention control,and an integrated array of four chemiresistor (CR) sensors coated with Au-thiolate monolayer-protected nanoparticles (MPN).MPN-CR array response patterns are used with retention times to identify eluting vapors.Air is used as the carrier gas.Calibrations of 20 common indoor air contaminants gave LODs in the range of 0.05 ng/g～0.53 ng/g for a 1 L sample volume.Results of preliminary analyses of characteristic VOCs generated from U.S.currency as well as vapor-phase markers of environmental tobacco smoke (ETS) at low-or sub-ng/g levels are presented.
文摘A high performance CMOS band-gap voltage reference circuit that can be used in interface integrated circuit of microsensor and compatible with 0. 6 μm ( double poly) mix process is proposed in this paper. The circuit can be employed in the range of 1. 8 - 8 V and carry out the first-order PTAT ( proportional to absolute temperature) temperature compensation. Through using a two-stage op-amp with a NMOS input pair as a negative feedback op-amp,the PSRR ( power supply rejection ratio) of the entire circuit is increased,and the temperature coefficient of reference voltage is decreased. Results from HSPICE simulation show that the PSRR is - 72. 76 dB in the condition of low-frequency,the temperature coefficient is 2. 4 × 10 -6 in the temperature range from - 10 ℃ to 90 ℃ and the power dissipation is only 14 μW when the supply voltage is 1. 8 V.
基金the NNSFC(No.19772014)the China National Foundation for Outstanding Young Researchers(No.19725207)Foundation for University Key Teacher by the Ministry of Education of China
文摘The purpose of this paper is to study the magnetomechanicalcharacteristic of a microsensor which is composed of a cantileveredbeam-plate with ferromagnetic films in order to measure the magneticfield from the deformation of plate when the microsensor is locatedin the magnetic field. To this end, a nu- merical approach made up ofthe finite element method for magnetic field and the finitedifference method for deflection of the microsensor is proposed toperform the numerical analysis of deflection under magnetoelasticinteraction. Some quantitative results of a case study for themagnetoelastic characteristic between the mag- netic field anddeflection of the microsensor in the magnetic field are given. Theresults show that this mi- crosensor can be used not only to measurethe magnitude of magnetic intensity, but also to possibly monitor thedirection of the vector of the magnetic field.
基金the financial support provided by the National Natural Science Foundation of China (NSFC No. U1733120, 61601469, 61674114, 61701475, 91743110, 21861132001)National Key R&D Program of China (2017YFF0204604, 2018YFE0118700)+4 种基金Tianjin Applied Basic Research and Advanced Technology (17JCJQJC43600)the 111 Project (B07014)the Initial Scientific Research Fund of State Key Laboratory of Precision Measuring Technology and Instruments, Tianjin University (No. Pilq1902)the Foundation for Talent Scientists of Nanchang Institute for Micro-technology of Tianjin Universitythe Open Research Fund of Key Laboratory of MEMS of Ministry of Education, Southeast University。
文摘To address the need for the on-site measurement of aging oil, in this paper, we propose an impedance-based microsensor for analyzing the moisture content in engine oil. Using a microfabrication process, we fabricated an interdigitated microelectrode and integrated it with a 3 D-printed microcontainer to produce a microsensor that can detect changes in the permittivity of oil. When the moisture content in oil increases, this sensor can detect the resulting change in the oil impedance, which is related to its permittivity, and then determine the degree to which the oil has aged. The test results show that the proposed microsensor has the advantages of being small and having high sensitivity, good accuracy, and the ability to be combined with hand-held instruments.The proposed method is expected to be used for the rapid, low cost, on-site determination of oil aging.
基金supported by National Key R&D Program of China(No.2016YFA0200800)Shanghai Science and Technology Innovation Action Plan(No.19520744200)+1 种基金Natural Science Foundation of Shanghai(Nos.17ZR1410000,18ZR1415400)the financial support of State Key Laboratory of Transducer Technology of China(No.SKT1806)。
文摘Dihydronicotinamide adenine dinucleotide(NADH)is an important enzyme in all living cells,which is found to be abnormally expressed in cancer cells.Since it is redox-active,an electrochemical detection method would be suitable for monitoring its concentration in biological fluids.Here we present a strategy for specific determination of NADH in real human serum by using RhIr@MoS2 nanohybrids based microsensor.To implement the protocol,RhIr nanocrysrals are in-situ grown onto MoS2 interlayers forming a nanohybrid structure(RhIr@MoS2).After being locally deposited on an electrochemical microsensor,it could be used for the analysis of NADH.The developed RhIr@MoS2 nanohybrids based microsensor possesses the ability for analyzing NADH at the applied potential of 0.07 V(much lower than most reported values).The detection limit is evaluated as low as 1 nmol/L even in bovine serum albumin(BSA)media.In addition,the sampling analysis of human serum from cancer patients and health controls shows that the microsensor displays good diagnostic sensitivity and specificity,illustrating that this developed detection technique is a relatively accurate method for measuring NADH in biological fluids.The proposed electrochemical microsensor assay also owns the benefits of convenience,disposable and easy processing,which make it a great possibility for future point-of-care cancer diagnosis.
基金the Fundamental Research Funds for the Central Universities,National Natural Science Foundation of China(No.82302345).
文摘In vivo monitoring of animal physiological information plays a crucial role in promptly alerting humans to potential diseases in animals and aiding in the exploration of mechanisms underlying human diseases.Currently,implantable electrochemical microsensors have emerged as a prominent area of research.These microsensors not only fulfill the technical requirements for monitoring animal physiological information but also offer an ideal platform for integration.They have been extensively studied for their ability to monitor animal physiological information in a minimally invasive manner,characterized by their bloodless,painless features,and exceptional performance.The development of implantable electrochemical microsensors for in vivo monitoring of animal physiological information has witnessed significant scientific and technological advancements through dedicated efforts.This review commenced with a comprehensive discussion of the construction of microsensors,including the materials utilized and the methods employed for fabrication.Following this,we proceeded to explore the various implantation technologies employed for electrochemical microsensors.In addition,a comprehensive overview was provided of the various applications of implantable electrochemical microsensors,specifically in the monitoring of diseases and the investigation of disease mechanisms.Lastly,a concise conclusion was conducted on the recent advancements and significant obstacles pertaining to the practical implementation of implantable electrochemical microsensors.
基金financial support from the National Natural Science Foundation of China(Grants No.U2330206,No.U2230206,and No.62173068)the Natural Science Foundation of Guangxi Province(Grant No.AB24010157)+1 种基金the Sichuan Forestry and Grassland Bureau(Grant Nos.G202206012 and G202206012-2)Sichuan Science and Technology Program(Grant Nos.2024NSFSC1483,2024ZYD0156,2023NSFC1962,and DQ202412).
文摘In modern complex systems,real-time regression prediction plays a vital role in performance evaluation and risk warning.Nevertheless,existing methods still face challenges in maintaining stability and predictive accuracy under complex conditions.To address these limitations,this study proposes an online prediction approach that integrates event tracking sensitivity analysis with machine learning.Specifically,a real-time event tracking sensitivity analysis method is employed to capture and quantify the impact of key events on system outputs.On this basis,a mutualinformation–based self-extraction mechanism is introduced to construct prior weights,which are then incorporated into a LightGBM prediction model.Furthermore,iterative optimization of the feature selection threshold is performed to enhance both stability and accuracy.Experiments on composite microsensor data demonstrate that the proposed method achieves robust and efficient real-time prediction,with potential extension to industrial monitoring and control applications.
基金funded in part by the National Key R&D Program of China under Grant 2023YFC2410600in part by the National Natural Science Foundation of China under Grant 62301536 and Grant 62121003+2 种基金in part by the Youth Innovation Promotion Association CAS Grant 2023134 and Grant 2022121in part by the Shandong Province Science and Technology Small and Medium-sized Enterprises Innovation Ability Improvement Project under Grant 2023TSGC0211in part by the Instrument Research and Development of CAS under Grant PTYQ2024BJ0009.
文摘Meeting the growing demands for accuracy,resolution and response time of high-pressure microsensors applicated in ocean science and petroleum industry,this paper developed a silicon resonant high pressure microsensor based on volume compressed sensing with dual resonators supported by micro beams.In operation,the frequency of resonators shifts while the volume of microsensor compressed under high pressure.A couple of micro beams were introduced to support resonators and protect resonators from buckling in high pressure.At the meanwhile,the theoretical model of micro beams was established.Based on the expression between geometric parameters of micro beams and pressure sensitivity of resonators,the micro beams of the two resonators were modified that results in different pressure sensitivities of two resonators,which effectively performed temperature self-compensation.An eutectic bonding is adopted for wafer vacuum packaged.Dealing with potentially complex hydraulic measurement,the microsensors were surrounded by silicone oil and sealed with a corrugated diaphragm and a base.The pressure sensitivities of fabricated microsensors were quantified as 0.003 kHz/MPa(~30 ppm/MPa)of Resonator Ⅰ and−0.118 kHz/MPa(~−1311 ppm/MPa)of Resonator Ⅱ under 20℃,which match with theoretical analysis.Finally,the accuracy of this microsensors is better than 0.01%FS with temperature self-compensation under the pressure range of 0.1~70 MPa from−10℃to 50℃,along with a response time better than 10 ms and a resolution of 100 Pa.This paper provided an effective structure of micro beams for resonant high-pressure microsensors combined with volume compressed sensing,derived the quantitative relationship between key structural parameters and sensitivity,and performed a possibility of high accuracy and high resolution measurements of a much wider pressure range.
文摘This paper presents a single-chip 3D electric field microsensor, in which a sensing element is set at the center to detect the Z-axis component of an electrostatic field. Two pairs of sensing elements with the same structure are arranged in a cross-like configuration to measure the X- and Y-axis electrostatic field components. An in-plane rotary mechanism is used in the microsensor to detect the X-, Y-, and Z-axis electrostatic field components simultaneously. The proposed microsensor is compact and presents high integration. The microsensor is fabricated through a MetalMUMPS process. Experimental results show that in the range of 0-50 kV/m, the linearity errors of the microsensor are within 5.5%, and the total measure- ment errors of the three electrostatic field components are less than 14.04%.
基金Project supported by the National Natural Science Foundation of China(No.60843005)the Basic Research Foundation of Beijing Institute of Technology,China(No.20070142018)
文摘A novel low-pass filter that consists of a switched capacitor filter （SCF） and its antialiasing prefilter and smoothing postfilter is proposed for a microsensor signal processing system, which is used in separation point detection on the surface of micro air vehicles. In the system, the filter is not only applied to finish the function of filtering but also used as the front end antialiasing filter of the over sampling analog-to-digital converter. This proposed implementation mostly relies on the design of a high-precision SCF employing a correlated double sampling technique and optimisation switches. Simultaneously, the multiple-loop feedback low pass filter with good high frequency attenuation characteristics is applied as the pre- and postfilter. The design is implemented in the Central Semiconductor Manufacturing Corporation （CSMC） 0.5 μm double-poly three-metal （2P3M） 3 chip die area occupies only 0.39 mm2 and dissipatesl.53 mW. 3 V CMOS technology, with satisfactory results, The
文摘This paper presents a high precision CMOS opamp suitable for ISFET readout. The opamp is tailored to provide a constant bias condition for ISFET as part of the readout circuits and,hence,is compatible for single chip integration with the sensor. A continuous time auto-zero stabilization technique is studied and employed, with the aim of suppressing the low frequency noises, including the offset voltage, 1/f noise, and temperature drift. The design is based on a 0.35μm CMOS process. With a 3.3V power supply,it maintains a DC open loop gain of more than 100dB and an offset voltage of around 11μV,while the overall power dissipation is only 1.48mW. With this opamp, a pH microsensor is constructed, of which the functionality is verified by experimental tests.
