Abstract: A ruthenium oxide electrode. The ruthenium oxide electrode includes a substrate, a ruthenium oxide film formed thereon, and a conductive wire connecting to the ruthenium oxide film. The invention also provides a method of fabricating the ruthenium oxide electrode.

Abstract: An amperometric sensor for uric acid and a manufacturing method thereof are disclosed, in which polyacrylamide is used to fix catalase, uricase and ferrocenecarboxylic acid on a working electrode. In determining concentration of uric acid, hydrogen peroxide is produced when enzyme and uric acid react with each other and then a reduction current generated from enzyme on the electrode with an external voltage 200 mV applied is detected. In determining concentration of uric acid, a concentration range of 2.5-20 mg/dl is achieved and sensibility of the sensor in a linear portion is 5.17 uAcm?2(mg/dl)?1. In addition, reaction time required for the reaction between enzyme and uric acid is 5.17 uAcm?2(mg/dl)?1.

Abstract: A uricase enzyme biosensor and fabrication method thereof. The uricase enzyme biosensor includes a metal oxide semiconductor field effect transistor, a sensing unit including a substrate, a titanium dioxide film formed thereon and a uricase enzyme sensing film formed on the titanium dioxide film, and a conductive wire connecting with the metal oxide semiconductor field effect transistor and the sensing unit. The invention also provides a sensing system and a sensing circuit including the biosensor.

Abstract: This invention provides a pCO2 sensor, and more particularly, a potentiometric pCO2 sensor. The potentiometric pCO2 sensor has a substrate, a solid ion-sensing layer on the substrate, a solid electrolyte layer on the solid ion-sensing layer, and a gas-permeable layer on the solid electrolyte layer. In addition, the gas-permeable layer allows air molecules to diffuse through, the solid electrolyte layer change the pH value thereof according to the CO2 concentration in the diffusing air molecules, and the solid ion-sensing layer senses the pH change of the solid electrolyte layer to generate a sensing signal. By doing so, the quantity of the CO2 dissolved in the liquid can be measured.

Abstract: A pH sensor is disclosed, including conductive glass, a SnO2 film formed on the conductive glass, and a field effect transistor (FET) with a gate coupled to the SnO2 film. When the SnO2 film contacts a liquid with a predetermined voltage, voltage between the liquid and the SnO2 film varies according to pH of the liquid, thereby changing channel current of the FET. The pH of the liquid can thus be determined according to the channel current.

Abstract: In this invention, a separative structure of the ion-selecting electrode is applied to fabricate the dual type potentiometric biosensor for creatinine detection. According to the fabrication process, the creatinine enzyme is immobilized onto a conductive layer of a substrate of pH sensing membrane and ammonium ion-selecting membrane. The conductive layer provides with a sensing region and a non-sensing region. A conductive line is extended from the conductive layer for using as an external electrical contact point. The dual type potentiometric creatinine biosensor was fabricated by using the enzyme immobilization method onto the surface of the selecting membrane of sensing membrane of pH sensing electrode and creatinine sensor.

Abstract: A reference pH sensor, the preparation and application thereof. The reference pH sensor is an extended gate field effect transistor (EGFET) structure and comprises a metal oxide semiconductor field effect transistor (MOSFET) on a semiconductor substrate, a sensing unit comprising a substrate, a solid-state conductive sensing layer on the substrate, and a polypyrrole layer on the solid-state conductive sensing layer, and a metal wire connecting the MOSFET and the sensing unit.

Abstract: Preparation of a pH sensor, the prepared pH sensor, system comprising the same, and measurement using the system. The pH sensor is an extended gate field effect transistor (EGFET) structure. The preparation includes the steps of providing an extended gate ion sensitive field effect transistor comprising an extended gate region, forming a titanium nitride film on the extended gate region by RF sputtering deposition to obtain a pH sensor.

Abstract: A biosensor containing ruthenium, measurement using the same, and the application thereof. The biosensor comprises an extended gate field effect transistor (EGFET) structure, including a metal oxide semiconductor field effect transistor (MOSFET), a sensing unit comprising a substrate, a layer comprising ruthenium on the substrate, and a metal wire connecting the MOSFET and the sensing unit.

Abstract: The present invention discloses a method and an apparatus of the drift calibration of sensors. The method includes shifting the sensing signal and differential technology to remove the drift signal by time during a long measuring. The apparatus includes two voltage sensors and readout circuits, a signal-shifting circuit and a differential circuit, and the apparatus is used for outputting the response signal without time drifting.

Abstract: A PbTiO3/SiO2-gated ISFET device comprising a PbTiO3 thin film as H+-sensing film, and a method of forming the same. The PbTiO3 thin film is formed through a sol-gel process which offers many advantages, such as, low processing temperature, easy control of the composition of the film and easy coating over a large substrate. The PbTiO3/SiO2 gated ISFET device of the present invention is highly sensitive in aqueous solution, and particularly in acidic aqueous solution. The sensitivity of the present ISFET ranges from 50 to 58 mV/pH. In addition, the disclosed ISFET has high linearity. Accordingly, the disclosed ISFET can be used to detect effluent.

Abstract: A method of fabricating an electrode assembly of a sensor is described. The sensor has a field effect transistor. The electrode assembly is separated from the field effect transistor by only a conductive line. The sensor is functioned to detect different glucose concentrations. A solid layer of tin oxide is deposited on a substrate board. A ?-D-glucose oxidase and polyvinylalchol bearing styrylpyridinium groups are placed in 100 ?l of sulfuric acid, to form an enzyme mixture. The enzyme mixture is dropped on the solid layer of tin oxide. The enzyme mixture is dried. The enzyme mixture is exposed to a UV ray. The enzyme mixture is dried and stabilized. The enzyme mixture is immersed in a sulfuric buffer.

Abstract: A potassium/sodium ion sensing device applying an extended-gate field effect transistor, which using an extended-gate ion sensitive field effect transistor (EGFET) as base to fabricate a potassium/sodium ion sensing device, using the extended gate of the extended-gate ion sensitive field effect transistor as a signal intercept electrode, and immobilizing the hydro-aliphatic urethane diacrylate (EB2001) intermixed with electronegative additive, potassium ionophore, sodium ionophore, and the like, to fabricate a potassium/sodium ion sensing electrode. The present invention utilizes the photocurability and good hydrophilicity of the hydro-aliphatic urethane diacrylate (EB2001), and fixes potassium/sodium ionophore, can obtain a non-wave filter, single-layer, stable signal potassium and sodium ion sensor.

Abstract: In this invention, an extended gate FET with a tin dioxide membrane is applied to fabricate a berberine sensor. There are two methods for fabricating the berberine sensor. First, it is mixed by the macromolecule polymer and electrocatalytic activities. The membrane is adsorbed on the SnO2/ITO glass and the berberine sensor is completed. Second, a polymer is used to immobilize enzyme on the substrate and detect the berberine. In this invention, the extended gate field effect transistor of the SnO2/ITO glass is applied to fabricate a durable berberine detection electrode. One of the berberine sensors that is macromolecule polymer, the optimal measurement environment is in distilled water and the best response curve can be realized, the detection rang is from 1×10?3M to 5×10?7M and the linear range is about 121.47 mV/pC. The berberine sensor based on the enzyme that optimal measurement environment is in 0.1M phosphate buffer solution at pH7.4 and better response curves can be obtained.

Abstract: The present discloses an ion sensor and its readout circuit. The sensor includes potentiometric, amperometric ion sensors or dual mode electrochemical sensor. The dual mode electrochemical sensors can be measured by the same measurement circuit system. The dual mode sensors are extended gate ion sensitive field effect transistors and amperometric biosensors. The measurement circuit system is adaptable to the different mode sensors.

Abstract: A titanium oxide extended gate field effect transistor (EGFET) device and fabricating method thereof. Titanium oxide is formed on an EGFET by sputtering, coating a detection membrane therefor. Current-voltage relationships at different pH values are also measured via a current measuring system. Sensitivity parameter of the titanium oxide EGFET is calculated according to a relationship between a pH value and a gate voltage.

Abstract: A method for fabricating an array pH sensor and a readout circuit device of such array pH sensor are implemented by utilizing an extended ion sensitive field effect transistor to construct the array pH sensor and related readout circuit. The structure of the array sensor having this extended ion sensitive field effect transistor comprises a tin dioxide/metal/silicon dioxide multi-layer structure sensor and a tin dioxide/indium tin oxide/glass multi-layer structure sensor and has excellent properties. Furthermore, the readout circuit and the sensor utilize two signal generators for controlling and reading signals. In particular, the sensor can be effective for increasing the accuracy of measurement and reducing the interference of noise.

Abstract: Methods for fabricating ion sensitive field effect transistors (ISFETs) with SnO2 extended gates. A SnO2 detection film is formed on a substrate by sol-gel technology to serve as an extended gate. The SnO2 detection film is electrically connected to a conductive wire, and an insulating layer is formed on the surface of the ISFET but part of the SnO2 detection film and the conductive wire are left exposed. The exposed conductive wire is electrically connected to a gate terminal of a MOS transistor.

Abstract: The present invention is a sensor for detecting urea using a separating-style structure of ion-selective electrode, in which an ammonium ion-selective membrane is immobilized on a conductive layer on the surface of a substrate, said conductive layer has a sensing region and a non-sensing region after packaged, and a conductive line is used to retrieve a sensing signal from said conductive layer. In the end, employing the enzyme immobilization method to immobilize a urea enzyme onto ammonium ion-selective membrane, thus the fabrication of a potentiometric urea sensor is completed.

Abstract: A SnO2 ISFET device and manufacturing method thereof. The present invention prepares SnO2 as the detection membrane of an ISFET by sol-gel technology to obtain a SnO2 ISFET. The present invention also measures the current-voltage curve for different pH and temperatures by a current measuring system. The temperature parameter of the SnO2 ISFET is calculated according to the relationship between the current-voltage curve and temperature. In addition, the drift rate of the SnO2 ISFET for different pH and hysteresis width of the SnO2 ISFET for different pH loop are calculated by a constant voltage/current circuit and a voltage-time recorder to measure the gate voltage of the SnO2 ISFET.