Scheduled System Maintenance:
On May 6th, single article purchases and IEEE account management will be unavailable from 8:00 AM - 5:00 PM ET (12:00 - 21:00 UTC). We apologize for the inconvenience.
By Topic

Sensors Journal, IEEE

Issue 2 • Date April 2006

Filter Results

Displaying Results 1 - 25 of 40
  • [Front cover]

    Publication Year: 2006 , Page(s): c1
    Save to Project icon | Request Permissions | PDF file iconPDF (117 KB)  
    Freely Available from IEEE
  • IEEE Sensors Journal publication information

    Publication Year: 2006 , Page(s): c2
    Save to Project icon | Request Permissions | PDF file iconPDF (35 KB)  
    Freely Available from IEEE
  • Table of contents

    Publication Year: 2006 , Page(s): 237 - 238
    Save to Project icon | Request Permissions | PDF file iconPDF (44 KB)  
    Freely Available from IEEE
  • A time-based VLSI potentiostat for ion current measurements

    Publication Year: 2006 , Page(s): 239 - 247
    Cited by:  Papers (28)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (424 KB) |  | HTML iconHTML  

    A time-based CMOS integrated potentiostatic control circuit has been designed and fabricated. The design maintains a constant bias potential between the reference and working electrodes for an amperometric chemical sensor. A technique of converting input currents into time for amperometric measurements is proposed. This technique eliminates current amplifying circuitry, reduces matching problems, and increases dynamic range while saving on area and power consumption. Redox currents ranging from 1 pA to 200 nA can be measured with a maximum nonlinearity of ±0.1% over this range. The design can be used to generate cyclic voltammograms for an electrochemical reaction by sweeping the voltages across a range specified by the user. Analog inputs are processed and digital outputs are generated without requiring a power-hungry A/D converter. A prototype chip has been fabricated in the 0.5-μm AMI CMOS process. Experimental results are reported showing the performance of the circuit as a chemical sensor. View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • Rapid diagnostic barcode system for codetection of multiple protein markers

    Publication Year: 2006 , Page(s): 248 - 253
    Cited by:  Papers (7)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (688 KB) |  | HTML iconHTML  

    An ultrasensitive immunodiagnostic readout method based on an electrochemical analysis is presented. Different inorganic quantum dot (QD) nanocrystals (ZnS, CdS, and PbS) are tagged to antibodies for the on-site voltammetric stripping measurements of multiple antigen targets. The multiprotein electrical sensing capability is coupled to the amplification feature of anodic stripping voltammetric transduction and with an efficient magnetic removal (to minimize nonspecific adsorption and cross-reactivity effects). Sandwich-immunoassay formats were performed using model proteins (β2-microglobulin, myoglobin, and human serum albumin). These encoding QD tracers with distinct redox potential yield highly sensitive and selective stripping peaks at -1.11 V (Zn), -0.67 V (Cd), and -0.52 V (Pb) at the mercury-film screen printed carbon electrode (versus Ag/AgCl reference). The position and size of these peaks reflect the identity and risk level of the corresponding antigen marker. The favorable signal-to-noise characteristics of the response for the initial 25-ng/mL mixture indicate a detection limit of ca. 10 ng/mL far below the early warning range and allow a reliable determination of very low protein concentrations. Such analog peaks of the QDs were converted to simple and rapid barcode signals. The digital readout system can code 215 electrically tuned barcodes to mark different protein analytes and to be useful for a wireless communication system. View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • Nonspecific binding removal from protein microarrays using thickness shear mode resonators

    Publication Year: 2006 , Page(s): 254 - 261
    Cited by:  Papers (11)  |  Patents (2)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (1600 KB) |  | HTML iconHTML  

    Nonspecific binding is a universal problem that reduces bioassay sensitivity and specificity. We demonstrate that ultrasonic waves, generated by 5-MHz quartz crystal resonators, accelerate nonspecifically bound protein desorption from sensing and nonsensing areas of micropatterned protein arrays, controllably and nondestructively cleaning the micropatterns. Nonsensing area fluorescent intensity values dropped by more than 85% and sensing area fluorescent intensity dropped 77% due to nonspecific binding removal at an input power of 14 W. After patterning, antibody films were many layers thick with nonspecifically bound protein, and aggregates obscured patterns. Quartz crystal resonators removed excess antibody layers and aggregates leaving highly uniform films, as evidenced by smaller spatial variations in fluorescent intensity and atomic force microscope surface roughness values. Fluorescent intensity values obtained after 14-W QCR operation were more repeatable and uniform. View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • Study on the disposable urea biosensors based on PVC-COOH membrane ammonium ion-selective electrodes

    Publication Year: 2006 , Page(s): 262 - 268
    Cited by:  Papers (5)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (424 KB) |  | HTML iconHTML  

    A potentiometric urea biosensor is prepared by the immobilization of urease directly onto the surface of a solid-state ammonium ion-selective electrode. The enzyme is immobilized by entrapment method onto a nonactin membrane that incorporated carboxylated polyvinylchloride. The same method of immobilization method is adopted to compare the characteristics of urea biosensors based on ammonium ion-selective electrodes with those based on pH-sensitive electrodes, using the same tin-oxide (SnO2)/indium tin-oxide glass substrate. Urea biosensors based on ammonium ion-selective electrodes respond quickly and stably to changes in urea concentrations between 0.026 and 10 mM. The slope in the linear range is around 55.56±3.15 mV/decade and the detection limit is around 5 μM. The effect of urea biosensors with different pH values is considered, and the characteristics of urea biosensors based on ammonium ion-selective electrodes are described. Additionally, the experimental results from the determination of the urea using biosensors based on pH-sensitive electrodes and ammonium ion-selective electrodes are compared and discussed. View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • Solid-state urea biosensor based on the differential method

    Publication Year: 2006 , Page(s): 269 - 275
    Cited by:  Papers (4)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (432 KB) |  | HTML iconHTML  

    In this paper, the solid-state urea biosensor was successfully fabricated based on the differential method, which contains three parts: the SnO2/ITO glass electrode used as the pseudoreference electrode; the SnO2/ITO glass electrode used as the contrast electrode; and the urease/SnO2/ITO glass electrode used as the enzyme electrode. Correspondingly, this solid-state urea biosensor was fabricated based on the SnO2/ITO glass electrode, whose simple fabrication process reduces the cost of fabricating the solid-state biosensor. Additionally, as revealed in the experimental results, the solid-state urea biosensor has good sensing characteristics between 5 and 80 mg/dl. After fabricating a successful solid-state urea biosensor, an array sensing system was designed to enhance the precision of the solid-state urea biosensor, which comprises four parts: the biosensor system, the input buffer circuit, the differential circuit, and the weighted sum circuit. As indicated in the experimental results of the array sensing system, the sensing characteristic of the array sensing system is similar to the mean sensing characteristic from four solid-state biosensors. Therefore, the sensing signal of the solid-state urea biosensor can be averaged using the array sensing system. In summary, this study successfully investigated a solid-state urea biosensor and designed an array sensing system to increase the precision of solid-state urea biosensors. View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • CMOS Monolithic Metal–Oxide Gas Sensor Microsystems

    Publication Year: 2006 , Page(s): 276 - 286
    Cited by:  Papers (22)  |  Patents (1)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (2280 KB) |  | HTML iconHTML  

    This paper presents two mixed-signal monolithic gas sensor microsystems fabricated in standard 0.8- \mu\hbox {m} CMOS technology combined with post-CMOS micromachining to form the microhotplates. The on-chip microhotplates provide very high temperatures (between 200 ^\circ C and 400 ^\circ C), which are necessary for the normal operation of metal–oxide sensing layers. The first microsystem has a single-ended architecture comprising a microhotplate (diameter of 300 \mu\hbox {m} ) and a digital proportional-integral-derivative (PID) microhotplate temperature controller. The second microsystem has a fully-differential architecture comprising an array of three microhotplates (diameter of 100 \mu\hbox {m} ) and three digital PID microhotplate temperature controllers (one controller per microhotplate). The on-chip digital PID temperature controllers can accurately adjust the microhotplate temperatures up to 400 ^\circ C with a resolution of 2 ^\circ C. Further, both microsystems feature on-chip logarithmic converters for the readout of the metal–oxide resistors (which cover a measurement range between 1 \hbox {k$\Omega$ } and 10 \hbox {M$\Omega$ } ), 10-bit A/D converters, anti-aliasing filters, 10-bit D/A converters, I ^2 C serial interfaces, and bulk-chip temperature sensors. Carbon monoxide (CO) concentrations in the sub-parts-per-million (ppm) range are detectable, and a resolution of 0.2 ppm CO has been achieved. View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • Pd-oxide- Al0.24Ga0.76As (MOS) high electron mobility transistor (HEMT)-based hydrogen sensor

    Publication Year: 2006 , Page(s): 287 - 292
    Cited by:  Papers (8)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (800 KB) |  | HTML iconHTML  

    An interesting hydrogen sensor based on an Al0.24Ga0.76As Schottky barrier high-electron mobility transistor with a catalytic Pd metal/oxide/semiconductor is fabricated and demonstrated. In comparison with traditional Schottky diodes or capacitance-voltage type hydrogen sensors, the studied device exhibits larger current variation, lower hydrogen detection limit, and shorter transient hydrogen response time. Besides, good hydrogen-sensing properties, such as significant drain current change, threshold voltage shift, and transconductance change of transistor behaviors, are obtained. Therefore, the studied device provides the promise for high-performance solid-state hydrogen sensors, optoelectronic integrated circuits, and microelectromechanical system applications. View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • Amorphous silicon two-color microbolometer for uncooled IR detection

    Publication Year: 2006 , Page(s): 293 - 300
    Cited by:  Papers (16)  |  Patents (6)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (704 KB) |  | HTML iconHTML  

    This paper describes the modeling and design of two-color microbolometers for uncooled infrared (IR) detection. The goal is to develop a high resolution IR detector array that can measure the actual temperature and color of an object based on two spectral wavelength regions. The microbolometer consists of high temperature amorphous silicon (a-Si:H) thin film layer held above the substrate by Si3N4 bridge. A thin NiCr absorber with sheet resistance of 377 Ω/sqr is used to enhance the optical absorption in the medium and long IR wavelength windows. A tunable micromachined Al-mirror was suspended underneath the detector. The mirror is switched between two positions by the application of an electrostatic voltage. The switching of the mirror between the two positions enables the creation of two wavelength response windows, 3-5 and 8-12 μm. A comparison of the two response wavelength windows enables the determination of the actual temperature of a viewed scene obtained by an IR camera. The microbolometer is designed with a low thermal mass of 1.65×10-9 J/K and a low thermal conductance of 2.94×10-7 W/K to maximize the responsivity Rv to a value as high as 5.91×104 W/K and detectivity D* to a value as high as 2.34×109 cm Hz12//W at 30 Hz. The corresponding thermal time constant is equal to 5.62 ms. Hence, these detectors could be used for 30-Hz frame rate applications. The extrapolated noise equivalent temperature difference is 2.34 mK for the 8-12 μm window and 23 mK for the 3-5 μm window. The calculated absorption coefficients in the medium and long IR wavelength windows before color mixing are 66.7% and 83.7%. However, when the color signals are summed at the output channel, the average achieved absorption was 75%. View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • Piezoresistive pressure sensing by porous silicon membrane

    Publication Year: 2006 , Page(s): 301 - 309
    Cited by:  Papers (7)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (904 KB)  

    In this paper, the piezoresistive pressure-sensing property of porous silicon has been reported. The pressure sensitivity of a porous silicon membrane of 63% porosity and 20-μm thickness has been observed to be about three times more than that of a conventional bulk silicon membrane of the same dimensions. The increased sensitivity is attributed to the improvement in piezoresistance due to quantum confinement in the porous silicon nanostructure. The piezoresistive coefficient of porous silicon is estimated for the first time and is observed to be about 50% larger than that of monocrystalline silicon for a 63% porosity porous silicon membrane. The response time has also been studied and observed to be significantly shorter. Power dissipation of the porous silicon pressure sensor is also much less compared to that of commercial bulk silicon piezoresistive pressure sensors. View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • Theory of direct frequency output vibrating gyroscopes

    Publication Year: 2006 , Page(s): 310 - 315
    Cited by:  Papers (3)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (320 KB) |  | HTML iconHTML  

    Vibrating gyroscopes are instruments for measuring the angular velocity of a system with respect to an inertial reference frame. Most currently available vibrating gyroscopes are based on the excitation of a reference vibration in the plane of a vibrating structure, and the amplitude detection of the vibration normal to the plane induced by the Coriolis effect, which is proportional to the angular velocity of the applied rotation. This paper describes a new vibrating gyroscope based on the simultaneous driving of the two modes of vibration (in plane and out of plane) and the detection of resonance frequencies. It is shown, in this paper, that the resonance frequencies of the two modes vary with the applied angular velocity, and that the difference between them is approximately proportional to the applied angular velocity. It is demonstrated that this kind of gyroscopes presents a lock-in effect related to the natural frequencies and the driving electronics. The results obtained are fundamental to the design of this kind of gyroscopes. View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • Fabrication and testing of bulk micromachined silicon carbide piezoresistive pressure sensors for high temperature applications

    Publication Year: 2006 , Page(s): 316 - 324
    Cited by:  Papers (23)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (992 KB) |  | HTML iconHTML  

    This paper explores the development of high-temperature pressure sensors based on polycrystalline and single-crystalline 3C-SiC piezoresistors and fabricated by bulk micromachining the underlying 100-mm diameter (100) silicon substrate. In one embodiment, phosphorus-doped APCVD polycrystalline 3C-SiC (poly-SiC) was used for the piezoresistors and sensor diaphragm, with LPCVD silicon nitride employed to electrically isolate the piezoresistor from the diaphragm. These piezoresistors fabricated from poly-SiC films deposited at different temperatures and doping levels were characterized, showing -2.1 as the best gauge factor and exhibited a sensitivities up to 20.9-mV/V*psi at room temperature. In a second embodiment, epitaxially-grown unintentionally nitrogen-doped single-crystalline 3C-SiC piezoresistors were fabricated on silicon diaphragms, with thermally grown silicon dioxide employed for the piezoresistor electrical isolation from the diaphragm. The associated 3C-SiC/SiO2/Si substrate was fabricated by bonding a (100) silicon wafer carrying the 3C-SiC onto a silicon wafer with thermal oxide covering its surface. The 3C-SiC handle wafer was then etched away in KOH. The diaphragm was fabricated by time etching the silicon substrate. The sensors were tested at temperatures up to 400°C and exhibited a sensitivity of 177.6-mV/V*psi at room temperature and 63.1-mV/V*psi at 400°C. The estimated longitudinal gauge factor of 3C-SiC piezoresistors along the [100] direction was estimated at about -18 at room temperature and -7 at 400°C. View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • A tubular piezoelectric vibrator gyroscope

    Publication Year: 2006 , Page(s): 325 - 330
    Cited by:  Papers (6)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (872 KB) |  | HTML iconHTML  

    This paper proposes a vibrator gyroscope made of a piezoelectric tube, which has the same configuration as that used for the tri-axial sensors and actuators developed in our previous paper. The gyroscopic operation is the same as a circular rod, but the polarization (in thickness direction of the shell) and, accordingly, the electrode arrangement are much simpler. Wireless LAN arrangement is devised for remote data access with which the measurement is possible for the gyroscope under rotation. The experimental results are compared with the numerical simulation with three-dimensional finite-element calculation. The discrepancy between the measured and the experimental is found to depend on the asymmetrical deformation of the structure, and the cause is clearly demonstrated via simulation. This shows the usefulness of the numerical modeling to investigate the cause, in which the parameters of dimensions and boundary conditions can easily change. View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • Fabrication of a planar polymeric deformation Bragg sensor component by excimer laser radiation

    Publication Year: 2006 , Page(s): 331 - 339
    Cited by:  Papers (1)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (1888 KB) |  | HTML iconHTML  

    Polymethylmethacrylate is irradiated by a UV-laser in order to modify its optical properties photochemically. Thus, by a lithographic method, the refractive index can be locally increased in a controllable way permitting the manufacturing of integrated-optical waveguiding and dispersive structures at the surface of a planar polymer chip. By this method, a polymeric Bragg sensor in integrated-optical form was fabricated by the UV-light of an excimer laser. The surface topography and the functional properties of the planar polymeric deformation Bragg sensor have been examined. Experiments concerning the evanescent field of the sensor have also been carried out in order to clarify the Bragg reflection mechanism. View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • The van der Pauw stress sensor

    Publication Year: 2006 , Page(s): 340 - 356
    Cited by:  Papers (19)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (1224 KB) |  | HTML iconHTML  

    Piezoresistive sensors fabricated on (100) and (111) silicon surfaces are capable of measuring from four to all six components of the stress state at a point on the surface of an integrated circuit die. Such resistor-based sensors have been successfully designed and fabricated on these wafer planes and have been used successfully for measurement of die stresses in electronic packages by many research teams. In this paper, classical van der Pauw (VDP) structures, traditionally used for sheet resistance measurement, are shown to provide more than three times the sensitivity of standard resistor sensors. A single four-terminal VDP device replaces two resistor rosette elements and inherently utilizes the high-accuracy four-wire resistance measurement method. Theoretical expressions are developed for the change in resistance of the VDP device as a function of the individual stress components resolved in wafer coordinate systems on both the (100) and (111) silicon surfaces, and it is predicted theoretically that VDP devices will exhibit more than three times higher sensitivity to stress than standard resistor sensors. Design, fabrication, and experimental characterization of VDP and resistor test structures are presented for both silicon surfaces, and numerical simulation is used to help resolve discrepancies between theory and experiment. Sources of experimental error are identified, and the 3.16 times sensitivity enhancement of the VDP device is confirmed. View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • Superconducting induction magnetometer

    Publication Year: 2006 , Page(s): 357 - 364
    Cited by:  Papers (4)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (808 KB) |  | HTML iconHTML  

    An attempt to generalize the current knowledge of passive magnetic field transducers- SQUID and induction sensors (ISs) (MAFCOPS)-and to incorporate elements of both designs in order to find a way to improve their performance data (PD) by creating, in theory, a combined transducer- superconducting induction magnetometer (SIM). State-of-the-art IS design is shown with two modifications for applications in outer space-LF with sensitivity threshold (ST) 5 pT/√Hz÷5 fT/√Hz in frequency range (FR) 20 Hz÷16 kHz and HF with ST 0.5 pT/√Hz÷1 fT/√Hz in FR 10 kHz÷10 MHz. The superconducting field-effect transistor (SuFET) is incorporated into a wide-band IS device in order to acquire an ST below 1 fT/√Hz in the FR from small values of Hertz to tens of megahertz (0.1÷107 Hz). The proposed magnetometer circuit consists of both a room-temperature or cooled (up to superconductive) pickup coil (PC) and a SuFET. Both the transfer function and the ST for SIM are analytically investigated proceeding from the equivalent and noise circuit, respectively. The sensitivity improvement of some SIM variants is shown in comparison with other state-of-the-art MAFCOPS. Constructional and operational distinctions of the designed sensor are explained. View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • Development and analysis of a PCB vector 2-D magnetic field sensor system for electronic compasses

    Publication Year: 2006 , Page(s): 365 - 371
    Cited by:  Papers (5)  |  Patents (12)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (1056 KB) |  | HTML iconHTML  

    A high-sensitivity vector two-dimensional (2-D) magnetic sensor system for low magnetic field measurements has been realized and tested. The system, made in PCB technology, consists of a double-axis Fluxgate magnetic sensor and the readout electronic circuitry, based on second-harmonic detection. The amorphous magnetic materials Vitrovac 6025X (25 μm thick) and Vitrovac 6025Z (20 μm thick) were used as the ferromagnetic core of the sensor. By applying a sinusoidal excitation current having a 450-mA peak at 10 kHz with Vitrovac 6025Z, the measured magnetic sensitivity was about 1.25 mV/μT. This value seems to be adequate for the Earth's magnetic field detection (±60 μT). The full-scale linearity error was about 1.5%. By using the thicker Vitrovac 6025X and a sinusoidal excitation current having a 600-mA peak at 10 kHz, a maximum sensitivity of approximately 1.68 mV/μT with a linearity error of about 1.55% full scale in the range of ±60 μT were measured. Due to the use of commercially available ferromagnetic materials, the vector 2-D magnetic sensor system presented is characterized by a very simple fabrication process, thus allowing low-cost devices to be designed. View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • On a new principle of a smart multisensor based on magnetic effects

    Publication Year: 2006 , Page(s): 372 - 379
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (848 KB) |  | HTML iconHTML  

    In this paper, a new principle of a smart sensor is proposed, based on three different magnetic effects or operational modes, using the same sensor topology, which consists of a magnetic wire as sensing core, two coils as excitation or search means, and two electric contacts at the ends of the magnetic wire. The magnetic effects currently involved are magnetostriction, magneto-impedance and re-entrant flux reversal. Operating the sensor in these three different modes separately and sequentially, one can obtain the response of the sensor related to three different physical quantities, such as stress, temperature, and field. This paper refers to the first experimental results based on this principle, thus initiating the research work in this field. It has been experimentally observed that the total output of the sensor in each one of the three different modes is equal to the product of each corresponding physical quantity function concerned, provided that a given threshold of the ambient field and preloaded stress is used to bias the sensing element. Therefore, the three unknown parameters of stress, temperature, and field can be determined from a 3×3 matrix equation. Other magnetic effects may also be involved. Furthermore, other physical quantities may also be determined, such as position, pressure, load, etc. View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • Gamma radiation nose system based on In2O3/SiO thick-film sensors

    Publication Year: 2006 , Page(s): 380 - 384
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (248 KB)  

    A prototype gamma radiation monitoring system based on In2O3/SiO thick-film sensors array was designed. Four sensors had an identical pn-heterojunction structure with different material compositions. These sensors were subjected to gamma radiation emitted by 137Cs source with an activity of 370 kBq. Changes in their current-voltage characteristics were recorded and compared. The performance parameters of the devices, such as sensitivity to γ radiation exposure and working dose region, were found to be highly dependent on the composition of the materials used. To cover a wider range of radiation and improve the overall sensitivity, an approach of using sensor arrays was utilized. A dynamic selection of the multiple sensors of various sensitivities and working dose ranges was implemented by applying a pattern recognition analysis. View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • 220-MHz monolithically integrated optical sensor with large-area integrated PIN photodiode

    Publication Year: 2006 , Page(s): 385 - 390
    Cited by:  Papers (8)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (968 KB)  

    We propose a PIN photodiode integrated in a BiCMOS process which combines a quantum efficiency of nearly 100% for red light, fast response times, and a low junction capacitance. Bandwidths of 720 MHz at 660 nm and 683 MHz at 850 nm are achieved for this PIN photodiode. It allows the design of fast optoelectronic integrated circuits for many advanced applications in optical sensing, optical storage systems, and optical data transmission for optical wavelengths ranging at least from 660 to 850 nm. Because of the low photodiode capacitance of 0.01 fF/μm2, it is possible to achieve high bandwidths, even with large photodetector areas. The proposed optical receiver employing a PIN photodiode with a diameter of 500 μm and a capacitance of only 2.2 pF attains a -3-dB bandwidth of 220 MHz, which corresponds to a maximum nonreturn-to-zero data rate of 300 Mbit/s. View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • Distance measurement sensor with PIN-photodiode and bridge circuit

    Publication Year: 2006 , Page(s): 391 - 397
    Cited by:  Papers (11)  |  Patents (3)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (616 KB)  

    The presented integrated optical distance measurement sensor works on the time-of-flight principle. The distance information is obtained from the correlation of received light and the transmitted signal. The PIN-bridge circuit concept ensures suppression of background light by equally charging and discharging the capacitor within one period, while integrating the wanted signal. The advantages of the included PIN-photodiode are high bandwidth f3 dB>1.35 GHz together with high responsivity R=0.36 A/W at 660 nm. A single distance measurement is performed in 2 ms. With averaging, an accuracy of better than 1% is achieved for distances up to 3.7 m. Effective pixel size is 250×200 μm2 having a fill-factor of ∼16%. The sensor was manufactured in a 0.6-μm BiCMOS process. View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • A 1.2-V 0.25-μm clock output pixel architecture with wide dynamic range and self-offset cancellation

    Publication Year: 2006 , Page(s): 398 - 405
    Cited by:  Papers (10)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (632 KB) |  | HTML iconHTML  

    A 10T/pixel CMOS digital pixel sensor with clock count output, ultra low supply voltage, and wide dynamic range is presented. The pixel fabricated by a standard 0.25-μm CMOS logic process comprises a reset transistor, a photo-diode, a comparator, and an inverter with pixel size of 9.4×9.4 μm2 and 24% fill factor. The amplified logarithmic output response similar to the light response of human eye is demonstrated in this work. The pixel can operate at a supply voltage as low as 1.2 V without affecting its output characteristics. The dynamic range of this cell limited by either the subsequent analog-to-digital circuit resolution or the rising and falling time of output clock is higher than 90 dB with an 8-bit resolution. View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • GaN-based p-i-n sensors with ITO contacts

    Publication Year: 2006 , Page(s): 406 - 411
    Cited by:  Papers (17)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (648 KB) |  | HTML iconHTML  

    Nitride-based p-i-n sensors with indium-tin-oxide electrodes on Mg-doped AlGaN/GaN strain layer superlattice structure were fabricated and characterized. It was found that the fabricated sensors exhibit small dark current and large reverse breakdown voltage. With an incident wavelength of 355 nm, we achieved a peak responsivity of 0.17 A/W which corresponds to 59% external quantum efficiency for sensors with 500°C annealed ITO(70 nm) p-contacts. View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.

Aims & Scope

The IEEE Sensors Journal is a peer-reviewed, monthly online/print  journal devoted to sensors and sensing phenomena

Full Aims & Scope

Meet Our Editors

Editor-in-Chief
Krikor Ozanyan
University of Manchester
Manchester, M13 9PL, U.K.