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Our group has integrated surface-enhanced Raman scattering (SERS) silver coated gold nanostars on an optical fiber. Fiber-based sensors are an in-situ technology that can simultaneously bring the sensor and light to the sample without disturbing the environment. This technology is a multi-use method that does not require complex sample preparation. Fiber sensors or optrodes, enable the detection of analytes in samples that are difficult to access. Additionally, optrodes allow for specific detection while evading background signals from non-target regions. The fiber-optrode was used to detect miRNA and illegal food additives.

The ability to monitor gene expression within living plants is of importance in many applications ranging from plant biology research to biofuel development; however, no method currently exists without requiring sample extraction. Herein, we report a multimodal imaging method based on plasmonic nanoprobes for in vivo imaging and biosensing of microRNA biotargets within whole plant leaves. This method integrates three different but complementary techniques: surfaceenhanced Raman scattering (SERS), X-ray fluorescence (XRF), and plasmonics-enhanced two-photon luminescence (TPL). The multimodal method utilizes plasmonic nanostars, which not only provide large Raman signal enhancement, but also allow for localization and quantification by XRF and plasmonics-enhanced TPL, owing to gold content and high two-photon luminescence cross-sections. For the sensing mechanism, inverse molecular sentinel (iMS) nanoprobes are used for SERS bioimaging of microRNA within Arabidopsis thaliana leaves to provide a dynamic SERS map of detected microRNA targets while also quantifying nanoprobe concentrations using XRF and TPL. This report lays the foundation for the use of plasmonic nanoprobes for in vivo functional imaging of nucleic acid biotargets in whole plants, a tool that will allow the study of these biotargets with previously unmet spatial and temporal resolution.

Reliability investigations were conducted after GaN-based LEDs were stressed in seawater vapour. Multiple electrical, optical, and material analyses on the fine nanostructures of the LED were examined. Results indicate that dark spots on the surface and etching trenches observed on the cross section might damage the quantum well and degrade LED performance. Dissolved sodium ions might diffuse and punch through the quantum well and be responsible for these spots and trenches.

This study designs a small arrayed Ultraviolet Light Emitting Diode (UV LED) curing system, using automatic electric power control circuit to drive 3 modules and 6 modules UV LED in wavelength of 365 nm and 385 nm, which is applicable to all sided adhesive material curing. The power output is controlled stably by the automatic electric power control circuit, so that the electric power is controlled stably, and the electric power is stable at ambient temperature10°C to 40°C, and the stable value is as high as 95%.

This paper proposes a solution to the excessive area penalty associated with traditional buffer direct injection (BDI) for single pixel. The proposed solution reduces the area and power consumption of BDI to combine the direct injection (DI) within a shared architecture, while a dual-mode readout circuit expands the functionality and performance of the array readout circuit of infrared sensor. An experimental array of 10 × 8 readout circuits was fabricated using TSMC 2P4M 0.35 μm 5 V technology. Measurements were obtained using a main clock with a frequency of 3 MHz and power consumption of 9.94 mW. The minimum input current was 119 pA in BDI and 1.85 pA in DI. The signal swing was 2 V, the root mean square noise voltage was 1.84 mV, and the signal-to-noise ratio was 60 dB. This approach is applicable to mid- and long-band sensors to increase injection efficiency and resolution.

In this study, a urea biosensor was prepared by the immobilization of urease onto the sensitive membrane of an extended-base bipolar junction transistor. The pH variation was used to detect the concentration of urea. The SnO2/ITO glass, fabricated by sputtering SnO2 on the conductive ITO glass, was used as a pH-sensitive membrane, which was connected with a commercial bipolar junction transistor device. The gels, fabricated by the poly vinyl alcohol with pendent styrylpyridinium groups, were used to immobilize the urease. This readout circuit, fabricated in a 0.35-um CMOS 2P4M process, operated at 3.3V supply voltage. This circuit occupied an area of 1.0 mm × 0.9 mm. The dynamic range of the urea biosensor was from 1.4 to 64 mg/dl at the 10 mM phosphate buffer solution and the sensitivity of this range was about 65.8 mV/pUrea. The effect of urea biosensors with different pH values was considered, and the characteristics of urea biosensors based on EBBJT were described.

This study aims to investigate whether an amperometric biosensor in an array configuration can increase its signal-to-noise ratio (SNR) so as to increase its performance, like sensitivity. Uric acid biosensor (UAB) was used as an example in this study. Both single UAB (UAB-1 × 1) and UAB array (UAB-1 × 2 and UAB-1 × 3) were fabricated with uricase immobilized on commercial graphite working electrodes. The UAB showed an excellent (r2 > 0.96) linear response range (0–0.8 mM) and moderate response time (∼20 s). Results showed that the sensitivity and SNR of UAB can be significantly increased by the use of an array configuration. It was found that the sensitivity and SNR of the UAB-1 × 3 is significantly higher (p

The purpose of this study was to develop the anodized titanium oxide nanotubes (ATONs) as a pH electrode with amperometric and potentiometric method. Titanium oxide nanotubes film was produced on pure titanium piece by titanium anodization at room temperature. The best one ATONs electrode has a linear pH response approximately 53 mV/pH with potentiometric method and 13 A/pH with amperometric method in the concentration range between pH 2 and 12.

This study developed a multi-ions sensing system that includes pH, potassium, sodium, and chloride ion sensors with a wireless home-care system. The pH sensor was based on a tin oxide (SnO )/indium tin oxide (ITO) glass, and the potassium, sodium, and chloride ion sensors were based on the pH sensor with sensing membrane. The tin oxide (SnO) sensing membrane was deposited on indium tin oxide (ITO) substrate using a sputtering system. The sensing membranes of the ion sensors were prepared by mixing poly (vinyl chloride) (PVC), bis (2-ethylhexyl) sebacate (DOS), ionophores, and additives. According to the experimental results, sensitivities of the sensors all were over the value 51 mV/decade. The linear range of pH sensor was between pH2 and pH12, the linear ranges of potassium, sodium, and chloride sensors all were over from 1 mM to 1 M. Therefore, the multi-ions sensing system is suitable for monitoring of blood electrolytes. The correlations of the multi-ion sensors under different test solutions also were discussed. Moreover, this study also investigated sensors module, portable module, Bluetooth module, personal computer (PC) terminal, and portable unit of the wireless home-care system. A graphical measurement interface for data recorded and measurement results displayed was designed by National Instrument Lab-VIEW software. According to the experimental results, the measurement data by the wireless home-care system are near the real values. The wireless home-care system could successfully monitor and transmitted the sensing signals.

0.95 (Na0.5Bi0.5)TiO3–0.05 BaTiO3 + 2 wt% Bi2O3 (NBT–BT3) ceramic was used as a target and NBT–BT3 thin films were deposited at room temperature by changing the RF power from 75 W to 150 W. The thickness of the NBT–BT3 thin films increased from 203 to 478 nm as the RF power increased from 75 W to 150 W. At 75 W RF power, the deposited NBT–BT3 thin films displayed defective surfaces, whereas at RF power ≧ 100 W, the NBT–BT3 thin films displayed smooth surfaces. The grain sizes also increased with increasing RF power. In addition, the remanent polarization and saturation polarization increased with increasing RF power. The coercive field first increased, reached a maximum at 100 W, then decreased with increasing RF power.

A potentiometric glucose biosensor based on a SnO2/ITO/PET substrate is presented in this study. The sensing membrane of SnO2 is coated on ITO/PET substrate by utilized radio frequency (RF)-sputtering method of semiconductor fabrication. The potentiometric glucose biosensor is established on an FET-type pH sensor. Therein, the glucose oxidase (GOD) and chitosan/multi-wall carbon nano-tubes (chitosan/MWCNTs) are immobilized by 3-glycidoxypropyl trimethoxysilane (3-GPTS). Finally, the drift characteristic and calibration curve of the potentiometric pH sensor and potentiometric glucose biosensor is discussed in the following article. We find the nonideal effect of device reduced significantly, due to the coating of SnO2 thin film.

A double potassium and sodium ions sensor based on separated extended gate field effect transistor (SEGFET) and a new entrapment method are proposed in this study. Having high sensitivity, reproducibility, and a simple manufacturing process, the sensors are quickly able to supply information and detect human blood within an abnormal range. The sensing membranes were fabricated using a Poly(vinyl chloride) carboxylated (PVC-COOH) matrix; sodium ionophore (B12C4) or potassium ionophore (valinomycin). The sensitivity of ion-selective biosensors is 42.55 mV/decade for Na+ between 1 M and 10-7 M, 42.75 mV/decade for K+ between 1 M and 10-6 M.

It has been known that drift and hysteresis resulted from the slow response of the pH electrodes. These inherent drawbacks handicap the application of the pH electrodes. Thus, the time-dependent slow response of the tin oxide pH electrode was modeled by mathematical expression. In this study, the three time-constant model was utilized to fit the drift behavior of the tin oxide pH electrode. Besides combining with the three time-constant model and the concept of network analysis, the hysteresis model was derived. According to the experimental results, the modeled hysteresis width was close to the measured hysteresis width. The drift behavior and the hysteresis width of the tin oxide pH electrode were linked by the time-constant model. In other words, the hysteresis width can be predicted by the time-constant model of the drift behavior

In this paper, the solid-state urea biosensor was successfully fabricated based on the differential method, which contains three parts: the SnO/sub 2//ITO glass electrode used as the pseudoreference electrode; the SnO/sub 2//ITO glass electrode used as the contrast electrode; and the urease/SnO/sub 2//ITO glass electrode used as the enzyme electrode. Correspondingly, this solid-state urea biosensor was fabricated based on the SnO/sub 2//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.

In previous investigations, different preparation methods of the pH electrode influenced pH-sensing characteristics. Hence, this study attempted to employ the tin oxide (SnO2) membrane in fabricating a pH electrode by the sputtering method, whose substrate was based on the indium tin oxide (ITO) glass substrate, and employing the two-point calibration method proved the pH-sensing characteristic. Furthermore, to define the effective sensing area of the pH electrode, experimental results and simulation results were employed. According to results, enough sensing area increased the pH sensitivity stability of the pH electrode and 4 mm 2 was the effective sensing area in fabricating a SnO2 pH electrode. After the effective fabrication process was proved, the SnO 2 pH electrode had linear pH response and higher stability as it compared with the commercial pH glass electrode. Consequently, this study investigated an effective SnO 2 pH electrode by the sputtering method. © 2004 Elsevier B.V. All rights reserved.

This study employs the tin oxide (SnO2) films as the sensing membrane for fabricating array sensors and combines these sensors with a real-time sensing system. Furthermore, the four-point probe, X-ray diffraction (XRD) and scanning probe microscopy (SPM) were applied in identifying the surface characterization of the SnO2 pH electrode. This study presents an array pH sensing system to obtain the signals from the SnO2 pH electrode. Additionally, an array sensing system reduces the errors of the single sensor and the real-time sensing system is employed as the testing system to reduce testing time. This paper presents the real-time sensing system that includes eight readout circuits and one data acquisition card using software (Labview) to control. Experimental results proved the surface characterization of the SnO2 pH electrode and this pH sensing system that monitored signals from each sensor simultaneously. Therefore, this paper presents an efficient real-time pH sensing system for array sensors.

Tin oxide thin films prepared by the radio frequency sputtering method were used as pH sensors based on the structure of the metal oxide electrode. The sensing characteristics and the hysteresis effect of the tin oxide pH electrode were studied. The hysteresis experiments were carried out under short- and long-loop circles, pH 7–4–7–10–7 and pH 7–2–7–12–6, respectively. Moreover, the hysteresis value was less than 7 mV in short-loop circle and the hysteresis value of pH 7 was 9 mV in acid side ( H A ) and 11 mV in alkali side ( H B ). The sensitivity of the tin oxide pH electrode was investigated between pH 2 and 12, whose pH sensitivity was about 59 mV/pH.

In this study, extended-gate field effect transistor (EGFET) was applied to fabricate disposable urea biosensor. And the 1.5 V low-voltage instrument amplifier was adopted to realize the portable urea biosensor. However, the difference between extended-gate field effect transistor and traditional ion-selective field effect transistor is the position of the sensitive membrane. The extended-gate field effect transistor was separated into two parts, which are the sensitive membrane and MOSFET. Hence, the MOSFET device can be designed to be a part of the readout circuit and the sensitive membrane was only put in the solution. Therefore, the configuration of the extended-gate field effect transistor can reduce the influence of the temperature, light and the erosion by the solutions. Besides, the configuration can reduce the cost substantially. The configuration of the extended-gate field effect transistor will raise the competitiveness to develop the disposable biosensor. The content of the urea in blood is one of the indexes to diagnose the renal efficiency. Then, the portable urea biosensor is the important expandable aspect. In this study, the gels, which are the poly vinyl alcohol with pendent styrylpyridinium groups, were used to immobilize the urease. The detection of the urea is based on the variation of pH value. Then, the dynamic range of the urea biosensor is from 0.31 to 120 mg/dl at the 5 mM phosphate buffer solution and the response time is about 2 min.

In this paper, we use the extended gate field effect transistor (EGFET) and the coated wire electrode (CWE) to design a differential pH-sensing device. The SnO/sub 2//ITO glass structure is the EGFET used as the pH sensor because of its excellent pH sensitivity of about 57.10 mV/pH. The contrast pH sensor is the polypyrrole/SnO/sub 2//ITO glass structure CWE, which has the lower pH sensitivity of about 27.81 mV/pH, and we use the third SnO/sub 2//ITO glass structure as the reference electrode to serve the base potential of the electrolyte solution. The pH sensitivity of this differential pH-sensing device is about 30.14 mV/pH and it is linear. Hence, this device is a good pH sensor. By using this technology, the differential pH-sensing device has a lot of advantages, such as simple fabrication, solid-state electrodes, easy packaging, low cost, etc.

A monolithic chip processing method is reported, which includes the ion sensitive field effect transistor (ISFET) of the pH sensor, p–n diode of temperature sensor and readout circuit using 0.5 μm double poly double metal (DPDM) standard CMOS product with UMC IC foundry company. We have designed a planar diffused silicon diode on a n-channel pH sensitive ISFET sensor to act as a temperature sensor for on-chip temperature measurement and compensation. Furthermore, the device integrated the dual sensors and readout circuit has the potential advantages of achieving, both the pH and temperature value display, with this process, ISFET’s temperature coefficient can be minimized.

In this paper, we present a method allowing industrial production of integrated ion sensitive field effect transistor (ISFET) sensor. An ASIC CMOS standard process is used to integrate the sensor and signal processing circuit; then the sensor is plated with the sensing membrane (SnO 2 ) by sputtering. The structure of the ISFET is novel SnO 2 /Al discrete gate. The discrete gate ISFET and the readout circuit were fabricated with a conventional standard CMOS IC process where no extra mask was required. The experimental data show that the SnO 2 /Al discrete gate ISFET sensors have a high linearity of 58 mV/pH in a concentration ranging from pH 2 to 10. The low offset and low power readout circuit for the discrete gate ISFETs pH sensor was designed and evaluated for monolithic in this study.

Silicon nitride (Si/sub 3/N/sub 4/) sensing gate pH-ion-selective field effect transistors (ISFETs) were treated by 2.54-GHz microwave O/sub 2/ plasma, the results show the ISFET sensitivity has an advantage up to 24% increment after the plasma treatment. Electron spectroscopy for chemical analysis (ESCA) is used to make sure that the plasma treatment is not just a native oxide cleaning procedure. The samples, which were immobilized with glutaraldehyde used as a bifunctional reagent and 3-aminopropy-Itricthoxysilane used as an adhesion promoter were studied. The binding force between the glucose oxidase and glutaraldehyde immobilized samples, and the element concentrations of nitrogen in 3-aminspropytriethoxysilane immobilized samples are higher which were treated by plasma.

In our research, glass was used as a substrate for an H + ion sensitive field effect transistor (ISFET). The sensitive characteristics of five structures for separate extended gate ion sensitive field effect transistors (EGFET) were studied. The components included tin oxide (SnO 2 )/aluminum/micro slide glass, tin oxide/aluminum/corning glass, indium tin oxide (ITO) glass, tin oxide/indium tin oxide glass and tin oxide/micro slide glass. Indium tin oxide (ITO) thin film was first time used as an H + ion sensitive film, which has a linear pH Nerstern response sensitivity, about 58 mV/pH, between pH 2 and 12. In addition, the sensing area effect of the tin oxide/glass, tin oxide/ITO glass and ITO glass structure is discussed. The results show that the tin oxide/ITO glass structure EGFET has the best drift, hysteresis and sensing area characteristics.

Ion-sensitive field effect transistor (ISFET) is a device composed of a conventional ion-sensitive electrode and MOSFET device, applied to the measurement of ion content in a solution. Extended gate field effect transistor (EGFET) is another structure to isolate FET from chemical environment. In this study, the ISFET was separated into two parts. Tin dioxide (SnO2), obtained by sputtering, is used as a pH-sensitive membrane for electrode, which is connected with a commercial MOSFET device in CD4007UB or LF356N. The experimental data show that this structure has a linear pH response of about 56–58 mV/pH in a concentration range between pH 2 and 12. In addition, it is easier to fabricate and package the sensitive membrane structure and the measurement is simple for the application of disposable biosensor.

The influence of temperature and optical effects on ISFET performance are important. In this study, the temperature characteristics of the SnO/sub 2//Si/sub 3/N/sub 4//SiO/sub 2//Si ISFET are investigated by the zero temperature coefficient (T.C.) adjustment and the dual FET's configuration, respectively. The result show that a zero T.C. of the SnO/sub 2/ gate ISFET can be achieved when the appropriate operation current was set. Subsequently, the T.C. of tin oxide membrane/electrolyte interface can be evaluated by the dual FETs configuration. On the other hand, due to the SnO/sub 2/ gate ISFET is sensitive to the light exposure, thus in order to improve this drawback, a multi-structure ISFETs: SnO/sub 2//Al/SiO/sub 2//Si/sub 3/N/sub 4//Si ISFETs have been developed. In this structure, aluminum is used as a light shield, and the tin oxide is used as a pH sensitive layer. The results show the ISFETs with aluminum as a light shield have low light sensitivity compared with ISFETs without aluminum as a light shield.

In this study, an amorphous tin oxide (SnO 2 ) obtained by thermal evaporation was used as a pH-sensitive material for pH-ISFETs. Capacitance–voltage (C–V) curves of the EIS diode were used to evaluate pH response of SnO 2 thin film. Subsequently, SnO 2 /SiO 2 gate ISFET was fabricated and pH sensitivity was determined through a shift in the threshold voltage of an ISFET sensor. The experimental data show that the SnO 2 /SiO 2 gate ISFET sensors have a linear pH response of about 58 mV pH −1 in a concentration range between pH 2 and pH 10. In addition, the other characteristics of this sensor, such as temperature effect, drift effect, hysteresis and response time were also investigated in this paper.

A new CMOS current readout structure for the infrared (IR) focal-plane-array (FPA), called the buffered gate modulation input (BGMI) circuit, is proposed in this paper. Using the technique of unbalanced current mirror, the new BGMI circuit can achieve high charge sensitivity with adaptive current gain control and good immunity from threshold-voltage variations. Moreover, the readout dynamic range can be significantly increased by using the threshold-voltage-independent current-mode background suppression technique. To further improve the readout performance, switch current integration techniques, shared-buffer biasing technique, and dynamic charging output stage with the correlated double sampling circuit are also incorporated into the BGMI circuit. An experimental 128/spl times/128 BGMI readout chip has been designed and fabricated in 0.8 /spl mu/m double-poly-double-metal (DPDM) n-well CMOS technology. The measurement results of the fabricated readout chip under 77 K and 5 V supply voltage have successfully verified both readout function and performance improvement. The fabricated chip has the maximum charge capacity of 9.5/spl times/10/sup 7/ electrons, the transimpedance of 2.5/spl times/10/sup 9/ /spl Omega/ at 10 nA background current, and the arrive power dissipation of 40 mW. The uniformity of background suppression currents can be as high as 99%. Thus, high injection efficiency, high charge sensitivity, large dynamic range, large storage capacity, and low noise can be achieved In the BGMI circuit with the pixel size of 50/spl times/50 /spl mu/m/sup 2/. These advantageous characteristics make the BCMI circuit suitable for various IR FPA readout applications with a wide range of background currents.

Rotating prism-pair scanning is a conventional method used to achieve large angles with a straight-line configuration. A disadvantage of prism scanners for line scanning is that the sinusoidal scan produces a non-linear image. We use a laser-diode encoding technique to carry out real-time image linearization in a rotating prism-pair scanning system. In this study, we report on the results obtained in a thermal image system.

Ga/sub 0.51/In/sub 0.49/P/In/sub 0.15/Ga/sub 0.85/As/GaAs pseudomorphic doped-channel FETs exhibiting excellent DC and microwave characteristics were successfully fabricated. A high peak transconductance of 350 mS/mm, a high gate-drain breakdown voltage of 31 V and a high maximum current density (575 mA/mm) were achieved. These results demonstrate that high transconductance and high breakdown voltage could be attained by using In/sub 0.15/Ga/sub 0.85/As and Ga/sub 0.51/In/sub 0.49/P as the channel and insulator materials, respectively. We also measured a high-current gain cut-off frequency f/sub t/ of 23.3 GHz and a high maximum oscillation frequency f/sub max/ of 50.8 GHz for a 1-/spl mu/m gate length device at 300 K. RF values where higher than those of other works of InGaAs channel pseudomorphic doped-channel FETs (DCFETs), high electron mobility transistors (HEMTs), and heterostructure FETs (HFETs) with the same gate length and were mainly attributed to higher transconductance due to higher mobility, while the DC values were comparable with the other works. The above results suggested that Ga/sub 0.51/In/sub 0.49/P/In/sub 0.15/Ga/sub 0.85/As/GaAs doped channel FET's were were very suitable for microwave high power device application.

An unpassivated InAs p-i-n photodetector with excellent performance at room temperature was demonstrated. The zero-bias resistance area products of the diode with 720-nm thick i-layer are 8.1 /spl Omega/-cm/sup 2/ at room temperature and as high as 1.3 M /spl Omega/-cm/sup 2/ at 77 K. At 77 K, the diode exhibits a breakdown voltage exceeding 13 V. When tested under a 500 K blackbody source, the measured detectivity limited by Johnson noise is 1.2/spl times/10/sup 10/ cm-Hz/sup 1/2 //W at room temperature and 8.1/spl times/10/sup 11/ cm-Hz/sup 1/2 //W at 77 K. To our knowledge, this is the best data for a room temperature infrared detector.

A new current readout structure for the infrared (IR) focal-plane-array (FPA), called the switch-current integration (SCI) structure, is presented in this paper. By applying the share-buffered direct-injection (SBDI) biasing technique and off focal-plane-array (off-FPA) integration capacitor structure, a high-performance readout interface circuit for the IR FPA is realized with a pixel size of 50/spl times/50 /spl mu/m/sup 2/. Moreover, the correlated double sampling (CDS) stage and dynamic discharging output stage are utilized to improve noise and speed performance of the readout structure under low power dissipation. In experimental SCI readout chip has been designed and fabricated in 0.8-/spl mu/m double-poly-double-metal (DPDM) n-well CMOS technology. The measurement results of the fabricated readout chip at 77 K with 4 and 8 V supply voltages have successfully verified both the readout function and the performance improvement. The fabricated chip has a maximum charge capacity of 1.12/spl times/10/sup 8/ electrons, a maximum transimpedance of 1/spl times/10/sup 9/ /spl Omega/, and an active power dissipation of 30 mW. The proposed CMOS SCI structure can be applied to various cryogenic IR FPA's.

The purpose of this study was to develop novel nanoscale biosensors using titania nanotubes (TNTs) made by anodization. Titania nanotubes were produced on pure titanium sheets by anodization at room temperature. In this research, the electrolyte composition ethylene glycol 250 mL/NH4F 1.5 g/DI water 20 mL was found to produce the best titania nanotubes array films for application in amperometric biosensors. The amperometric results exhibit an excellent linearity for uric acid (UA) concentrations in the range between 2 and 14 mg/dL, with 23.3 (µA·cm−2)·(mg/dL)−1 UA sensitivity, and a correlation coefficient of 0.993. The glucose biosensor presented a good linear relationship in the lower glucose concentration range between 50 and 125 mg/dL, and the corresponding sensitivity was approximately 249.6 (µA·cm−2)·(100 mg/dL)−1 glucose, with a correlation coefficient of 0.973.

This paper proposes dual-mode buffer direct injection (BDI) and direct injection (DI) readout circuit design. The DI readout circuit has the advantage of being a simple circuit, requiring a small layout area, and low power consumption. The internal resistance of the photodetector will affect the photocurrent injection efficiency. We used a buffer amplifier to design the BDI readout circuit since it would reduce the input impedance and raise the injection efficiency. This paper will discuss and analyze the power consumption, injection efficiency, layout area, and circuit noise. The circuit is simulated using a TSMC 0.35 um Mixed Signal 2P4M CMOS 5 V process. The dimension of the pixel area is 30×30 μm. We have designed a 10×8 array for the readout circuit of the interlaced columns. The input current ranges from 1 nA to 10 nA, when the measurement current is 10 pA to 10 nA. The integration time was varied. The circuit output swing was 2 V. The total root mean square noise voltage was 4.84 mV. The signal to noise ratio was 52 dB, and the full chip circuit power consumption was 9.94 mW.

A new output-controllable InSb infrared (i.r.) detector is proposed. The detector is fabricated by monolithically integrating an InSb p-n junction with an InSb p-channel enhancement mode metal oxide semiconductor field effect transistor (MOSFET). During operation, a photocurrent generated near the source junction is controllably switched to the drain terminal by a gate of the integrated MOSFET. The observed internal quantum efficiency in the ‘on’ state is as high as 85%. Photocurrent on-off ratios are between 260 and 730, improving with increasing channel length. For longchannel devices, the photocurrent in the ‘off’ state is limited by undesired leakage paths. The new structure can be used as an output-controllable i.r. detector.

A front‐illuminated long wavelength multiple quantum‐well infrared photodetector (QWIP) with backside gratings is successfully fabricated. The front illumination is achieved through the reflection of incoming light by etched gratings fabricated on the backside of the wafer. The detector is based on bound‐to‐continuum state transition in the quantum wells. The epitaxial structure is grown by molecular beam epitaxy. There are 30 periods of GaAs/AlGaAs quantum wells. The measured results show a detection peak at 8.7 μm and a cutoff wavelength of 10.3 μm. The dark current of QWIP is studied in the temperature range from 20 to 300 K. The dark current is found to be due to thermionic emission at low bias voltage and in the temperature range above 50 K, and due to tunneling in the low‐temperature range below 50 K and at a bias voltage above 1 V.

An InSb metal-oxide-semiconductor field effect transistor (MOSFET) with three different channel lengths 5, 15 and 30 /spl mu/m was fabricated successfully. The SiO/sub 2/ prepared by photo-enhanced chemical vapor deposition was used both as the gate insulator and the source/drain passivation layer to reduce the source/drain pn junction surface leakage current. The common-source current-voltage characteristics show breakdown voltage exceeding 2 V indicating excellent pn junction reverse characteristics. The capacitance-voltage and the transferred current versus gate voltage characteristics are discussed in detail to explain the geometry effect on the device performance. >

This paper presents the readout circuit based on Direct Injection (DI) and Capacitive Transimpedance Amplifier (CTIA). The hybrid type of CTIA and DI was adopted as the pixel circuit's design in this paper. The two different structures were combined into unit pixels, and each pixel has two modes of readout. Furthermore, the chip was produced with TSMC 2P4M 5V technology, and the array size is 10×8. The output swing is 2.1V and power consumption is 9.4 mW, according to measurement results. The Layout area is 40um × 40um, and the two modes are selected by an external pin. The dual mode structure enables single- and dual-band infrared sensors. The readout chip can operate in 2kHz ∼ 6MHz, and the input photocurrent range is 1pA ∼ 50nA, depending on integration time; thus, it can be suitable for various detectors.

This paper takes advantage of digital dimming auto-control pulse width drive Light-Emitting Diodes to let the light in terms of brightness fade to gray by degrees and have the effect of mixture of colors. Also, Light-Emitting Diodes in such three primary colors as red, green, and blue mix with one another to yield various colors. Therefore, better stability, simpler structure and better effect of dimming. Moreover, it succeeds in utilizing red, green, and blue Light-Emitting diodes at room temperature to change Color Rendering Index of the cool white Light-Emitting Diodes. The design of the circuit makes use of the manufacturing technique of Very Large Scale Integration to make the completion of Integrated Circuit (TSMC 0.35μm MIXED MODE 2P4M 3.3v process).

The brightness of a Light Emitting Diode is proportional to the forward current. Constant LED forward current provides brightness. Temperature is an important factor in LED color temperature. The color temperature varies when the temperature varies. Therefore, an advanced temperature control scheme is proposed. An Automatic Color Temperature Control Circuit with color temperature compensation is proposed. It is confirmed that the proposed system provides stable color temperature within a temperature range from -30℃ to 85℃.

Sr 0.6 Ba 0.4 Nb 2 O 6 (SBN) thin films were deposited using radio frequency (RF) magnetron sputtering method and post annealing in a conventional furnace. The annealing process had improved the crystallization and also had large influences on the crystalline orientation. As the annealing temperature increased from 600°C to 700°C, the diffraction intensities of (410) and (001) planes increased. Annealed at 800°C, the SBN thin films showed highly c-axis crystalline orientation of (001) plane. The influences of annealing temperatures on the electrical characteristics of the polarization-applied electric field curves, the capacitance-voltage curves, and the leakage current density-electric field curves were investigated.

The average particle sizes of nanoscale (Ba 0.8 Sr 0.2 )(Ti 0.9 Zr 0.1 )O 3 ceramic powder (nano-BSTZ) was approximately 73nm. Polyvinylidene fluoride (PVDF)/nano-BSTZ composite films with various contents of the nano-BSTZ were screen-printed on indium tin oxide glass substrates. From the XRD patterns, PVDF was the semicrystalline type polymer. The content of the nano-BSTZ increased from 10 wt% to 50 wt%, the dielectric constants of the PVDF/nano-BSTZ films slightly decreased with increasing measured frequency. The specific capacitance values of the PVDF/nano-BSTZ composite films mixing with 50 wt% nano-BSTZ was 11.6 nF/cm2 (measured at 1 kHz). Those results suggested that the PVDF/nano-BSTZ composite films were a good candidate to develop thinner embedded capacitor devices with higher capacitance value.

This study developed a multi-ion sensing system includes pH, potassium, sodium, and chloride ion sensors with a wireless home-care system. The pH sensor was based on a SnO 2 /ITO glass, and the potassium, sodium, and chloride ion sensors were based on the pH sensor with sensing membrane. Moreover, the wireless home-care system includes sensors module, portable module, Bluetooth module, personal computer (PC) terminal, and portable unit. According to the experimental results, the wireless system could successfully monitor and transmit the sensing signals.