Pub Date : 2007-09-24DOI: 10.1109/SENSOR.2007.4300453
Hyun-Joong Kim, Meng Zhang, B. Ziaie
This paper reports a new and simple way to fabricate biaxially stretchable interconnects. To increase the stretchability, two novel ideas are suggested. These include 1) a geometry of 2-D diamond shaped gold lines on a PDMS substrate, and 2) coverage of potentially breakable points with liquid alloy. Stretchability of up to 60% was obtained using these techniques.
{"title":"A Biaxially Stretchable Interconnect with Liquid Alloy Joints on Flexible Substrate","authors":"Hyun-Joong Kim, Meng Zhang, B. Ziaie","doi":"10.1109/SENSOR.2007.4300453","DOIUrl":"https://doi.org/10.1109/SENSOR.2007.4300453","url":null,"abstract":"This paper reports a new and simple way to fabricate biaxially stretchable interconnects. To increase the stretchability, two novel ideas are suggested. These include 1) a geometry of 2-D diamond shaped gold lines on a PDMS substrate, and 2) coverage of potentially breakable points with liquid alloy. Stretchability of up to 60% was obtained using these techniques.","PeriodicalId":23295,"journal":{"name":"TRANSDUCERS 2007 - 2007 International Solid-State Sensors, Actuators and Microsystems Conference","volume":"135 1","pages":"1597-1600"},"PeriodicalIF":0.0,"publicationDate":"2007-09-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"73467250","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2007-09-24DOI: 10.1109/SENSOR.2007.4300411
I. Yanagimachi, N. Nashida, K. Iwasa, H. Suzuki
Heavy metal ions in soil samples were analyzed by a novel method based on evaporative concentration. The detector chip had a microelectrode array as a working electrode and a Ag/AgCl reference electrode surrounded by a super-hydrophobic layer formed with polytetrafluoroethylene (PTFE) beads. A sample droplet formed on the electrode area was shrunk to concentrate the solution. Cd2+ , Pb2+ , and As3+ ions were analyzed by square wave anodic stripping voltammetry. By combining a protective layer and wet sample digestion, the heavy metal ions in soil samples could be analyzed. Correlation coefficients between the values obtained by this method and those by a conventional method was 0.982 (Pb2+), 0.969 (Cd2+), and 0.936 (As3+).
{"title":"Analysis of Heavy Metal Ions in Real Samples using a Concentrator Device with a Super-Hydrophobic Surface","authors":"I. Yanagimachi, N. Nashida, K. Iwasa, H. Suzuki","doi":"10.1109/SENSOR.2007.4300411","DOIUrl":"https://doi.org/10.1109/SENSOR.2007.4300411","url":null,"abstract":"Heavy metal ions in soil samples were analyzed by a novel method based on evaporative concentration. The detector chip had a microelectrode array as a working electrode and a Ag/AgCl reference electrode surrounded by a super-hydrophobic layer formed with polytetrafluoroethylene (PTFE) beads. A sample droplet formed on the electrode area was shrunk to concentrate the solution. Cd2+ , Pb2+ , and As3+ ions were analyzed by square wave anodic stripping voltammetry. By combining a protective layer and wet sample digestion, the heavy metal ions in soil samples could be analyzed. Correlation coefficients between the values obtained by this method and those by a conventional method was 0.982 (Pb2+), 0.969 (Cd2+), and 0.936 (As3+).","PeriodicalId":23295,"journal":{"name":"TRANSDUCERS 2007 - 2007 International Solid-State Sensors, Actuators and Microsystems Conference","volume":"19 1","pages":"1425-1428"},"PeriodicalIF":0.0,"publicationDate":"2007-09-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"74557365","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2007-09-24DOI: 10.1109/SENSOR.2007.4300689
V. Ferrara, B. Alfano, E. Massera, I. Nasti, G. Francia
A hydrogen sensor based on an array of palladium nanowires has been realized starting from a silicon substrate coated with a Si3N4 where an interdigitated electrode pattern has been fabricated using photolithography. Saturated palladium solution has been prepared and array of palladium nanowires has been formed applying at the electrodes a voltage signal. As grown Pd nanowires are conductive and do not exhibit any response to hydrogen. Their response can be activated after a treatment which modifies physical properties of Pd nanowires, improving their response. The array has been tested towards 4% H2 in nitrogen carrier. We have observed that the device response, at room temperature, is quite strong and reversible so that the sensor device seems to be useful for those applications where the Lower Explosive Limit needs to be controlled.
{"title":"Fabrication and Characterization of a Hydrogen Sensor Based on Palladium Nanowires","authors":"V. Ferrara, B. Alfano, E. Massera, I. Nasti, G. Francia","doi":"10.1109/SENSOR.2007.4300689","DOIUrl":"https://doi.org/10.1109/SENSOR.2007.4300689","url":null,"abstract":"A hydrogen sensor based on an array of palladium nanowires has been realized starting from a silicon substrate coated with a Si3N4 where an interdigitated electrode pattern has been fabricated using photolithography. Saturated palladium solution has been prepared and array of palladium nanowires has been formed applying at the electrodes a voltage signal. As grown Pd nanowires are conductive and do not exhibit any response to hydrogen. Their response can be activated after a treatment which modifies physical properties of Pd nanowires, improving their response. The array has been tested towards 4% H2 in nitrogen carrier. We have observed that the device response, at room temperature, is quite strong and reversible so that the sensor device seems to be useful for those applications where the Lower Explosive Limit needs to be controlled.","PeriodicalId":23295,"journal":{"name":"TRANSDUCERS 2007 - 2007 International Solid-State Sensors, Actuators and Microsystems Conference","volume":"10 1","pages":"2541-2544"},"PeriodicalIF":0.0,"publicationDate":"2007-09-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"87352076","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2007-09-24DOI: 10.1109/SENSOR.2007.4300476
N. Ramakrishnan, E. Johns, Yongjun Zhao, J. Kiely, M. Bedillion, P. Chu
Applications involving sub-nanometer, relative, in-plane motion between two substrates require precise control of gap-spacing between substrates for, both position-sensing as well as for signal transduction between the substrates. A method of passive gap-spacing control using MEMS-fabricated rigid spacers is proposed. A model to design a low-friction and low-wear interface between the sliding substrates is developed. Prototype parts with hard-coated interfaces and with and without lubrication were fabricated and tested. Sliding friction coefficients of 0.1-0.15 or less and wear life of millions of sliding cycles were achieved on prototype parts. Better results are predicted for MEMS-scale devices.
{"title":"Sliding Contact Micro-Bearing for Nano-Precision Sensing and Positioning","authors":"N. Ramakrishnan, E. Johns, Yongjun Zhao, J. Kiely, M. Bedillion, P. Chu","doi":"10.1109/SENSOR.2007.4300476","DOIUrl":"https://doi.org/10.1109/SENSOR.2007.4300476","url":null,"abstract":"Applications involving sub-nanometer, relative, in-plane motion between two substrates require precise control of gap-spacing between substrates for, both position-sensing as well as for signal transduction between the substrates. A method of passive gap-spacing control using MEMS-fabricated rigid spacers is proposed. A model to design a low-friction and low-wear interface between the sliding substrates is developed. Prototype parts with hard-coated interfaces and with and without lubrication were fabricated and tested. Sliding friction coefficients of 0.1-0.15 or less and wear life of millions of sliding cycles were achieved on prototype parts. Better results are predicted for MEMS-scale devices.","PeriodicalId":23295,"journal":{"name":"TRANSDUCERS 2007 - 2007 International Solid-State Sensors, Actuators and Microsystems Conference","volume":"71 1","pages":"1689-1692"},"PeriodicalIF":0.0,"publicationDate":"2007-09-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"83129069","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2007-09-24DOI: 10.1109/SENSOR.2007.4300682
Yu-Ching Lin, T. Ono, M. Esashi
A self-sensing cantilever of AT-cut quartz plate was developed to achieve a high sensitivity under various environments at room temperature. The cantilevers fabricated by deep reactive ion etching with metal electrodes at the both sides have the thicknesses of 20 mum. The external force at shear- vibration direction induces the resonant frequency changes at thickness-shear vibration mode. The frequency modulation (FM) detection of thickness-shear vibration was demonstrated and the sensitivity and noise lever were investigated.
{"title":"Self-Sensing Quartz-Crystal Cantilever for Nanometric Sensing","authors":"Yu-Ching Lin, T. Ono, M. Esashi","doi":"10.1109/SENSOR.2007.4300682","DOIUrl":"https://doi.org/10.1109/SENSOR.2007.4300682","url":null,"abstract":"A self-sensing cantilever of AT-cut quartz plate was developed to achieve a high sensitivity under various environments at room temperature. The cantilevers fabricated by deep reactive ion etching with metal electrodes at the both sides have the thicknesses of 20 mum. The external force at shear- vibration direction induces the resonant frequency changes at thickness-shear vibration mode. The frequency modulation (FM) detection of thickness-shear vibration was demonstrated and the sensitivity and noise lever were investigated.","PeriodicalId":23295,"journal":{"name":"TRANSDUCERS 2007 - 2007 International Solid-State Sensors, Actuators and Microsystems Conference","volume":"2013 1","pages":"2513-2516"},"PeriodicalIF":0.0,"publicationDate":"2007-09-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"86278801","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2007-06-10DOI: 10.1109/SENSOR.2007.4300524
J. Matsuo, T. Hizawa, K. Sawada, H. Takao, M. Ishida
We successfully fabricated a super high sensitivity charge transfer type pH sensor. The proposed pH sensor is possible to amplify the sensing signals without an external amplifier by accumulation cycle. The pH sensitivity was obtained 5048 mV/pH, which is approximately 100 times higher than the Ion Sensitive Field Effect Transistor (ISFET), which is the most familiar pH sensor using semiconductor. This is the highest sensitivity of pH in the past. The performance of this charge transfer type pH sensor is equal with glass electrode type pH sensor. In addition, the charge transfer type pH sensor has much possibility to exceed the glass electrode method.
{"title":"Charge Transfer Type pH Sensor with Super High Sensitivity","authors":"J. Matsuo, T. Hizawa, K. Sawada, H. Takao, M. Ishida","doi":"10.1109/SENSOR.2007.4300524","DOIUrl":"https://doi.org/10.1109/SENSOR.2007.4300524","url":null,"abstract":"We successfully fabricated a super high sensitivity charge transfer type pH sensor. The proposed pH sensor is possible to amplify the sensing signals without an external amplifier by accumulation cycle. The pH sensitivity was obtained 5048 mV/pH, which is approximately 100 times higher than the Ion Sensitive Field Effect Transistor (ISFET), which is the most familiar pH sensor using semiconductor. This is the highest sensitivity of pH in the past. The performance of this charge transfer type pH sensor is equal with glass electrode type pH sensor. In addition, the charge transfer type pH sensor has much possibility to exceed the glass electrode method.","PeriodicalId":23295,"journal":{"name":"TRANSDUCERS 2007 - 2007 International Solid-State Sensors, Actuators and Microsystems Conference","volume":"27 1","pages":"1881-1884"},"PeriodicalIF":0.0,"publicationDate":"2007-06-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"73882980","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2007-06-10DOI: 10.1109/SENSOR.2007.4300586
A. Pais, A. Banerjee, D. K. Bandi, D. Klotzkin, I. Papautsky
In this paper we present a novel, high-sensitivity, cost-effective cross-polarization scheme to filter out excitation light from a fluorescent dye emission spectrum. With this scheme, it is possible to achieve a detection limit of 10 nM which is a 1,000 fold reduction from previously published results. The concept is demonstrated using an inverted microscope with a halide lamp as the excitation source and an organic photodiode as the intensity detector. The excitation light is linearly polarized and used to illuminate a microfluidic device containing 1 muL of Rhodamine 6G dye dissolved in ethanol. The detector is shielded by a second polarizer, orientated orthogonally to the excitation light. The resulting emission signal was detected by the organic photodiode down to a concentration of 10 nM. This scheme opens the possibility to fabricating integrated microfluidic devices with fluorescence detection, suitable for point- of-care (POC) diagnostics, biomedical and environmental applications.
{"title":"High Sensitivity On-Chip Fluorescence Detection Based on Cross-Polarization and Thin-Film Organic Photodetectors","authors":"A. Pais, A. Banerjee, D. K. Bandi, D. Klotzkin, I. Papautsky","doi":"10.1109/SENSOR.2007.4300586","DOIUrl":"https://doi.org/10.1109/SENSOR.2007.4300586","url":null,"abstract":"In this paper we present a novel, high-sensitivity, cost-effective cross-polarization scheme to filter out excitation light from a fluorescent dye emission spectrum. With this scheme, it is possible to achieve a detection limit of 10 nM which is a 1,000 fold reduction from previously published results. The concept is demonstrated using an inverted microscope with a halide lamp as the excitation source and an organic photodiode as the intensity detector. The excitation light is linearly polarized and used to illuminate a microfluidic device containing 1 muL of Rhodamine 6G dye dissolved in ethanol. The detector is shielded by a second polarizer, orientated orthogonally to the excitation light. The resulting emission signal was detected by the organic photodiode down to a concentration of 10 nM. This scheme opens the possibility to fabricating integrated microfluidic devices with fluorescence detection, suitable for point- of-care (POC) diagnostics, biomedical and environmental applications.","PeriodicalId":23295,"journal":{"name":"TRANSDUCERS 2007 - 2007 International Solid-State Sensors, Actuators and Microsystems Conference","volume":"28 1","pages":"2127-2130"},"PeriodicalIF":0.0,"publicationDate":"2007-06-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"73934795","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2007-06-10DOI: 10.1109/SENSOR.2007.4300252
S. Ingebrandt, G. Wrobel, S. Eick, S. Schafer, A. Offenhausser
We describe a novel method for the non-invasive, electronic monitoring of the cell-substrate adhesion. We utilize open-gate field-effect transistor (FET) chips for our adhesion measurements. These chips were developed, fabricated, and previously used for the extracellular recording from electrogenic cells. We developed a miniaturized and portable 16-channel amplifier system, which monitors the electronic transfer function of the FETs. We present cellular adhesion measurements of HEK 293 cells on an individual cell level. The system can additionally be used to probe the viability of individual cells.
{"title":"Probing the Adhesion and Viability of Individual Cells with Field-Effect Transistors","authors":"S. Ingebrandt, G. Wrobel, S. Eick, S. Schafer, A. Offenhausser","doi":"10.1109/SENSOR.2007.4300252","DOIUrl":"https://doi.org/10.1109/SENSOR.2007.4300252","url":null,"abstract":"We describe a novel method for the non-invasive, electronic monitoring of the cell-substrate adhesion. We utilize open-gate field-effect transistor (FET) chips for our adhesion measurements. These chips were developed, fabricated, and previously used for the extracellular recording from electrogenic cells. We developed a miniaturized and portable 16-channel amplifier system, which monitors the electronic transfer function of the FETs. We present cellular adhesion measurements of HEK 293 cells on an individual cell level. The system can additionally be used to probe the viability of individual cells.","PeriodicalId":23295,"journal":{"name":"TRANSDUCERS 2007 - 2007 International Solid-State Sensors, Actuators and Microsystems Conference","volume":"1021 1","pages":"803-806"},"PeriodicalIF":0.0,"publicationDate":"2007-06-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"74142054","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2007-06-10DOI: 10.1109/SENSOR.2007.4300450
B. Bowers, J. Agashe, D. Arnold
In this work, samarium cobalt (SmCo) powder is utilized for the fabrication of micromagnetic structures embedded in silicon wafers. The fabrication process involves the dry packing of raw, magnetic powder (mean particle diameter of 5-10 mum) into etched cavities within the wafer. After the wafer is loaded with the powder, a 6 mum layer of polyimide is spun over the wafer's surface to seal the magnetic powder in place and permit the development of additional structures around the embedded magnets. The feature sizes achieved during the investigation range in thickness from 15 mum to the entire depth of the wafer (~ 500 mum), and in lateral dimensions from 150 mum to 600 mum. One set of processed micromagnets demonstrated a coercivity, Hc = 141 kA/m (1.8 kOe), remanence, Br = 0.52 T (5.2 kG), and maximum energy product, (BH)max = 23 kJ/m3 (2.9 MGOe).
{"title":"A Method to Form Bonded Micromagnets Embedded in Silicon","authors":"B. Bowers, J. Agashe, D. Arnold","doi":"10.1109/SENSOR.2007.4300450","DOIUrl":"https://doi.org/10.1109/SENSOR.2007.4300450","url":null,"abstract":"In this work, samarium cobalt (SmCo) powder is utilized for the fabrication of micromagnetic structures embedded in silicon wafers. The fabrication process involves the dry packing of raw, magnetic powder (mean particle diameter of 5-10 mum) into etched cavities within the wafer. After the wafer is loaded with the powder, a 6 mum layer of polyimide is spun over the wafer's surface to seal the magnetic powder in place and permit the development of additional structures around the embedded magnets. The feature sizes achieved during the investigation range in thickness from 15 mum to the entire depth of the wafer (~ 500 mum), and in lateral dimensions from 150 mum to 600 mum. One set of processed micromagnets demonstrated a coercivity, Hc = 141 kA/m (1.8 kOe), remanence, Br = 0.52 T (5.2 kG), and maximum energy product, (BH)max = 23 kJ/m3 (2.9 MGOe).","PeriodicalId":23295,"journal":{"name":"TRANSDUCERS 2007 - 2007 International Solid-State Sensors, Actuators and Microsystems Conference","volume":"107 1","pages":"1585-1588"},"PeriodicalIF":0.0,"publicationDate":"2007-06-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"74537677","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2007-06-10DOI: 10.1109/SENSOR.2007.4300404
B. Bahreyni, G. Wijeweera, C. Shafai, A. Rajapakse
This paper discusses the design of a sensitive micromachined electric field sensor. The sensor operation is based on chopping an incident electric field using a perforated shutter and then differentially measuring the induced charge on two sets of electrodes which are situated under the shutter. To lower the required actuation signal levels, thermal actuators are used to bring and keep the structure under resonance. The produced displacements are mechanically amplified to allow for relatively large displacements with small actuation signals. Simulation and experimental results are also presented. Fabricated devices have a linear response and are capable of measuring fields as small as 42 V/m.
{"title":"Design and Testing of a Field-Chopping Electric Field Sensor using Thermal Actuators with Mechanically Amplified Response","authors":"B. Bahreyni, G. Wijeweera, C. Shafai, A. Rajapakse","doi":"10.1109/SENSOR.2007.4300404","DOIUrl":"https://doi.org/10.1109/SENSOR.2007.4300404","url":null,"abstract":"This paper discusses the design of a sensitive micromachined electric field sensor. The sensor operation is based on chopping an incident electric field using a perforated shutter and then differentially measuring the induced charge on two sets of electrodes which are situated under the shutter. To lower the required actuation signal levels, thermal actuators are used to bring and keep the structure under resonance. The produced displacements are mechanically amplified to allow for relatively large displacements with small actuation signals. Simulation and experimental results are also presented. Fabricated devices have a linear response and are capable of measuring fields as small as 42 V/m.","PeriodicalId":23295,"journal":{"name":"TRANSDUCERS 2007 - 2007 International Solid-State Sensors, Actuators and Microsystems Conference","volume":"289 1","pages":"1397-1400"},"PeriodicalIF":0.0,"publicationDate":"2007-06-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"73095119","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}