111 results about "ISFET" patented technology

Methods and apparatus relating to very large scale FET arrays for analyte measurements. ChemFET (e.g., ISFET) arrays may be fabricated using conventional CMOS processing techniques based on improved FET pixel and array designs that increase measurement sensitivity and accuracy, and at the same time facilitate significantly small pixel sizes and dense arrays. Improved array control techniques provide for rapid data acquisition from large and dense arrays. Such arrays may be employed to detect a presence and/or concentration changes of various analyte types in a wide variety of chemical and/or biological processes. In one example, chemFET arrays facilitate DNA sequencing techniques based on monitoring changes in hydrogen ion concentration (pH), changes in other analyte concentration, and/or binding events associated with chemical processes relating to DNA synthesis.

Use of a pH sensor comprising an ion-sensitive field effect transistor (ISFET) to perform real time detection/quantification of nucleic acid amplification, e.g. polymerase chain reaction (PCR) nucleic acid amplification, based on detection of protons released during the primer extension phase.

Methods and apparatus relating to very large scale FET arrays for analyte measurements. ChemFET (e.g., ISFET) arrays may be fabricated using conventional CMOS processing techniques based on improved FET pixel and array designs that increase measurement sensitivity and accuracy, and at the same time facilitate significantly small pixel sizes and dense arrays. Improved array control techniques provide for rapid data acquisition from large and dense arrays. Such arrays may be employed to detect a presence and/or concentration changes of various analyte types in a wide variety of chemical and/or biological processes. In one example, chemFET arrays facilitate DNA sequencing techniques based on monitoring changes in the concentration of inorganic pyrophosphate (PPi), hydrogen ions, and nucleotide triphosphates.

The invention provides a CMOS and ISFET dual-mode image chemical sensor chip for high-throughput gene sequencing; the chip comprises a dual-mode pixel array, a row decoder/driver, a column decoder/driver, a column parallel gain adjustable amplifier, a column parallel single-slope analog-digital converter, a static random access memory, a sensitive amplifier, a low voltage differential signal readout module, a static register, a phase-locked loop, a ramp generator and a digital control current source. The chip comprises an image sensor and an ion sensitive field effective transistor (ISFET) produced by a standard semiconductor process, so that optical image acquisition and chemical pH value detection can be performed. A high-speed correlated double sampling signal readout circuit adapting to the image and chemical dual-mode sensing is provided to reduce a system error caused by the mismatch between threshold voltages VT of the sensors. The chip has the advantages of high accuracy and high throughput when applied in gene sequencing.

Disclosed is an ISFET comprising a H+-sensing membrane consisting of RF-sputtering a-WO3. The a-WO3/SiO2-gate ISFET of the present invention is very 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.

Methods and apparatuses relating to large scale FET arrays for analyte detection and measurement are provided. ChemFET (e.g., ISFET) arrays may be fabricated using conventional CMOS processing techniques based on improved FET pixel and array designs that increase measurement sensitivity and accuracy, and at the same time facilitate significantly small pixel sizes and dense arrays. Improved array control techniques provide for rapid data acquisition from large and dense arrays. Such arrays may be employed to detect a presence and/or concentration changes of various analyte types in a wide variety of chemical and/or biological processes.

Integrated ISFET signal amplifier in two modes includes following parts: difference amplifier is composed of Ma1 and Mb1; Ma2íóMb2 and Mc constitute bootstrap circuit; Current mirror image circuits M9, M8, M7, M2, M1; and source of current I1a, I1b, and I0. ISFET current type signal differential circuit includes ISFET amplifier and REFET amplifier, quasi reference electrode PRE, two pieces of follower amplifier M1 and M3. The invention is suitable to process signal input from ISFET sensor in high precision and larger dynamic range.

A CMOS or bipolar based Ion Sensitive Field Effect Transistor (ISFET) comprising an ion sensitive recess for holding a liquid wherein the recess is formed at least partly on top of a gate of the transistor. There is also provided a method of manufacturing an I on Sensitive Field Effect Transistor (ISFET) utilizing CMOS processing steps, the method comprising forming an ion sensitive recess for holding a liquid at least partly on top of a gate of the transistor.

A system, method and apparatus for determining a physiological condition within a mammal based on pH and/or temperature measurements. In one aspect, the invention is directed to an apparatus for measuring a physiological condition within a mammal comprising: a tubular housing extending along a longitudinal axis from a distal end to a proximal end, the housing having an internal cavity; a first opening in the elongated housing forming a first passageway into the internal cavity; an ion-sensitive field effect transistor (ISFET) for measuring pH within a body lumen of the mammal, the ISFET positioned in the internal cavity, the ISFET aligned with the first opening so that at least a portion of the ISFET is exposed via the first opening; and a first seal between the ISFET and the housing forming a hermetic seal about a perimeter of the first opening.

An electrochemical sensor has a sensor housing and an ion-sensitive field effect transistor (ISFET) with a source connection (S) and a drain connection (D). An ion-sensitive surface area (IS) on the front surface of the ISFET is immersible in a measuring medium. A clamping element serves to clamp the ISFET with its rear surface against an end surface of the sensor housing. The clamping element has a central opening leaving the ion-sensitive surface area (IS) exposed. A leak-tight circular connection between the clamping element and the sensor housing is formed by vibratory, preferably ultrasonic, welding. The ISFET is sandwiched between two rubber-elastic elements, at least one of which forms a leak-tight seal against penetration of the measuring medium from the ion-sensitive surface area (IS) to the source- and drain connections (S) and (D).

A method and an apparatus for measuring the temperature parameters of an ISFET that uses hydrogenated amorphous silicon as a sensing film, which uses the measurements of the temperature parameters and the source/drain current and gate voltage in an unknown solution to sense the ion concentration and the pH value of the unknown solution.

An electronic circuit for ion sensor with the body effect reduction includes a bridge-type floating source circuit provided with an input terminal, an output terminal reflecting the change in the potential dependent on ion concentration, and an ion-sensitive field effect transistor (ISFET) wherein one terminal of the ISFET is coupled with the output terminal; a current mirror for providing a current to the bridge-type circuit; a third transistor for receiving the operating current provided by the current mirror, identical to the current provided to the ISFET; a differential amplifying circuit, wherein one input terminal of the amplifying circuit is input with a reference voltage, and the other input terminal is coupled with the output of the bridge-type readout circuit; and a third amplifier to generate a differential output voltage compensated for the body effect, temperature and time drift effects.

The invention discloses a multi-parameter low-power-consumption current-mode ion sensitive field effect tube array sensor device which comprises an n*n ISFET (ion sensitive field effect tube) sensor array, a matrix selection switch for selecting ISFETs, an address decoder, a reference transistor (REFET) for temperature and common-mode drift compensation, a normal-phase current transmitter, an anti-phase current transmitter, a current mode analog-digital converter (ADC) and a voltage analog-digital converter (DAC). ISFETs, selected by an address selector, of a grid coverage sensitive film and REFETs, selected by the address selector, of a grid coverage passivation film form differential geminate transistors, and the current difference outputted by the differential geminate transistors is converted by the ADC into a digital voltage signal to be outputted. Compared with a voltage mode circuit, the device adopting a current mode detection circuit can work under low working voltage, and is low in circuit power consumption and large in dynamic range; in addition, by adopting the differential detection ways, the imbalance and the temperature drift of the device can be effectively inhibited; meanwhile, the non-ideal characteristics of an ISFET sensor, such as long-term drift, can be effectively compensated.

A mechanism is provided for enhancing the sensitivity of an ion-sensitive semiconductor device by creating a second gate coupled to a sense plate that can improve the amount of charge brought to the ion-sensitive semiconductor device conductivity modulated region (e.g., a channel region of an ISFET). This is accomplished by utilizing a buried dielectric layer associated with the ion-sensitive semiconductor device conductivity modulated region as the second gate dielectric. The buried dielectric layer is coupled to the sense plate using an isolated well region as a conductor that is coupled to metal layers extending to the sense plate. Some embodiments further use the buried dielectric layer as the sole gate dielectric for the semiconductor device, thereby allowing the traditional gate dielectric region to be coupled to a protection diode. This protection diode then protects the gate dielectric from plasma induced damage and electrostatic discharge.

The invention relates to the field of biological detection and discloses an electronic sensor and a gene detection method based on the electronic sensor. The electronic sensor comprises ISFET, a nano-wire channel between a source electrode and a drain electrode of the ISFET is provided with a first groove by etching, the bottom of the first groove is provided with nano-pores, or is provided with chemical molecules or is provided with nano-pores and chemical molecules arranged at the nano-pores so that it is avoided that the DNA molecules smoothly slide at a high rate from one side to the other side of the chemical molecules or the nano-pores without control, only after a single-chain DNA to be tested successfully matches a detection basic group, a basic group can be moved forward by the chemical molecules and a matching process of the detection basic group and the basic group of the single-chain DNA to be tested can be accurately detected so that the gene detection result is more accurate, a detection precision is high and detection sensitivity is high.

There is provided a semiconductor device for detecting a change in ion concentration of a sample and method of using same. The device comprises a plurality of Field Effect Transistors (FETs) coupled to a common floating gate and an ion sensing layer exposed to the sample and coupled to the floating gate. There may be other input voltages coupled to the floating gate.

The present invention provides a novel sensor for the estimation of total cholesterol in human blood serum using molecular imprint of cholesterol. Human blood serum contains 150-250 mg/dl cholesterol. The present invention provides a sensor device and a process for the fabrication of ISFET (Ion Selective Field Effect Transister) coated with molecular imprint of cholesterol on the SiO₂+Si₃N₄ dielectric gate of the said electrode. The molecular imprint of cholesterol (MIPC) anchored in to a silica matrix sensing material is identified as a sensing material which has specific selectivity towards the cholesterol in presence of other organic constituents in human blood serum.

The electrode assembly is provided with: a rod-like body 1 that extends along a predetermined axis ; a substrate that is formed with a through-hole penetrating between a front surface and a back surface and attached to a fore end part of the body; and a sensor chip for electrochemical measurement, which is attached on the back surface of the substrate such that a sensing part is exposed outside from the through-hole, wherein: on the back surface of the substrate, a wiring for obtaining an output signal from the ISFET chip is formed, and the sensor chip is attached to the wiring directly or closely; and the substrate is attached with being inclined with respect to the predetermined axis of the body, and thereby the front surface of the substrate forms at least a part of a fore end surface that is inclined with respect to the predetermined axis.

This invention relates to a device intended to perform various chemical determinations in several wet chemical processes commonly used in semiconductor applications, including, but not limited to, those referred to as front end of line (FEOL) cleans, back end of line (BEOL) cleans, and copper electroplating. The device provides continuous or near continuous sensing of critical parameters such as component concentrations and metallic impurity concentrations. The device is capable of storing data for transmission after completion of the process, or transmitting data in real time as it is acquired. The device makes use of ISFET's and ChemFET's coupled with reference electrodes to detect small variations in the chemical properties of various wet chemical processes. The device can further either store the data for later analyses or transmit the data in real or near real time for more temporal analysis and control.

An array of micro-chambers 220) with individual ion sensitive field effect transistors (ISFETs) (300) disposed therein for monitoring single cell activity in the microarray to determine the presence or absence of microorganisms in a sample (390). In addition to the presence or absence of a single cell, certain further embodiments contemplate monitoring cell behavior. Cell behavior includes the entire range of cell activity as well as cell response to changes in environmental conditions of changes in response due to the addition of sample constituents.

Dual-gate ion-sensitive field effect transistor (ISFET) and methods implementing the dual-gate ISFETs for disease diagnostics are disclosed herein. An exemplary method includes providing a biological sample to a dual-gate ISFET. The dual-gate ISFET includes a fluidic gate structure and a gate structure, where the fluidic gate structure and the gate structure are disposed over opposite surfaces of a device substrate. The method further includes generating enzymatic reactions from enzyme-modified detection mechanisms. The enzyme-modified detection mechanisms release ions into an electrolyte solution of the fluidic gate structure. The method further includes biasing the fluidic gate structure and the gate structure to generate an electrical signal as a sensing layer of the fluidic gate structure reacts with the ions. The electrical signal indicates an ion concentration in the electrolyte solution that correlates with a presence or a quantity of target analytes in the biological sample.