901results about How to "Reduce dark current" patented technology

A solid-state imaging device includes an array of pixels, each pixel includes: a pixel electrode; an organic layer; a counter electrode; a sealing layer; a color filter; a readout circuit; and a light-collecting unit as defined herein, the photoelectric layer contains an organic p type semiconductor and an organic n type semiconductor, the organic layer further includes a charge blocking layer as defined herein, an ionization potential of the charge blocking layer and an electron affinity of the organic n type semiconductor in the photoelectric layer has a difference of at least 1 eV, and the sealing layer includes a first sealing sublayer formed by atomic layer deposition and a second sealing sublayer formed by physical vapor deposition and containing one of a metal oxide, a metal nitride, and a metal oxynitride.

CMOS imaging sensors having fluorine-passivated structures to reduce dark current are disclosed together with methods of making thereof. The CIS comprises an array of pixels on a substrate, each pixel comprising a pinned photodiode, an isolation trench adjacent to the pinned photodiode, and a plurality of transistors. Methods of preparing a CIS comprise providing a source of fluorine (F) atoms, and annealing in the presence of the source of F atoms. After the annealing, at least one silicon-containing surface or region in the CIS comprises Si—F bonds and is fluorine passivated.

An avalanche photo-detector (APD) is disclosed, which can reduce device capacitance, operating voltage, carrier transport time and dark current as well as increasing response speed and output power. Thus, an avalanche photo-detector (APD) with high saturation power, high gain-bandwidth product, low noise, fast response, low dark current is achieved. The APD includes an absorption layer with graded doping for converting an incident light into carriers, an undoped multiplication layer for multiplying current by means of receiving carriers, a doped field buffer layer sandwiched between the absorption layer and the multiplication layer for concentrating an electric field in the multiplication layer when a bias voltage is applied, and an undoped drift layer sandwiched between the absorption layer and the field buffer layer for capacitance reduction.

A photoelectric conversion device includes, in the following order: a first electrode; an electron blocking layer; a photoelectric conversion layer containing a merocyanine dye; a hole blocking layer; and a transparent electrode as a second electrode, and an absorption maximum wavelength in a thin film absorption spectrum of the photoelectric conversion layer containing a merocyanine dye is within a range of from 400 to 520 nm.

A pixel circuit of an image sensor includes a photo-converting unit such as a photo-diode for generating charge from incident light. The pixel circuit also includes a charge storing capacitor for storing the charge generated by the photo-converting unit. The pixel circuit further includes a floating diffusion node that receives the charge from the charge storing unit after being reset. Thus, an image signal VSIG is generated after a reset signal VRES is generated from the pixel circuit.

CMOS image sensor and method for fabricating the same, the CMOS image sensor including a second conductive type semiconductor substrate having an active region and a device isolation region defined therein, wherein the active region has a photodiode region and a transistor region defined therein, a device isolating film in the semiconductor substrate of the device isolation region, a first conductive type impurity region in the semiconductor substrate of the photodiode region, the first conductive type impurity region being spaced a distance from the device isolation film, and a second conductive type first impurity region in the semiconductor substrate between the first conductive type impurity region and the device isolation film, thereby reducing generation of a darkcurrent at an interface between the photodiode region and a field region.

The invention relates to an ultraviolet detector, in particular to a visible-blind ultraviolet detector based on a Beta-Ga2O3/SiC heterojunction thin film and a fabrication method of the visible-blind ultraviolet detector. According to the fabrication method, a layer of Beta-Ga2O3 thin film is deposited on an n-type 6H-SiC substrate by a laser molecular beam epitaxial technique, and then a layer of Ti/Au thin film is deposited on the n-type 6H-SiC substrate and the Beta-Ga2O3 thin film through a mask by a radio frequency magnetron sputtering to be used as an electrode. The fabricated visible-blind ultraviolet detector has the advantages of stable performance, response sensitivity, small dark current and high potential application; and moreover, the fabrication method has the characteristics of high process controllability, simplicity in operation, high universality, restorability of repeated test and the like, and has great application prospect.

A backside illuminated image sensor comprises a sensor layer implementing a plurality of photosensitive elements of a pixel array, and an oxide layer adjacent a backside surface of the sensor layer. The sensor layer comprises a seed layer and an epitaxial layer formed over the seed layer, with the seed layer having a cross-sectional doping profile in which a designated dopant is substantially confined to a pixel array area of the sensor layer. The doping profile advantageously reduces dark current generated at an interface between the sensor layer and the oxide layer. The image sensor may be implemented in a digital camera or other type of digital imaging device.

The invention relates to an InAs/GaSb secondary category superlattice infrared detector. The infrared detector comprises: a substrate; a buffer ohmic contact layer, which is manufactured on the substrate; a first secondary category superlattice layer, which is manufactured on the buffer ohmic contact layer so as to enable table tops to be formed at two sides above the buffer ohmic contact layer; an intrinsic secondary category superlattice light absorption layer, which is manufactured on the first secondary category superlattice layer; a second secondary category superlattice layer, which is manufactured on the intrinsic secondary category superlattice light absorption layer; an ohmic contact layer, which is manufactured on the second secondary category superlattice layer; a passivation layer, which covers portions of the table tops at the two sides of the buffer ohmic contact layer, side surfaces of the first secondary category superlattice layer, the intrinsic secondary category superlattice light absorption layer, the second secondary category superlattice layer and the ohmic contact layer as well as two side surfaces on the ohmic contact layer; upper electrodes, which are manufactured at two sides of a light transmission opening; and lower electrodes, which are manufactured inside electrode windows. Specifically, the light transmission opening is arranged in the middle of the passivation layer covering the ohmic contact layer; and the electrode windows are respectively arranged on the two table tops at two sides of the passivation layer covering the buffer ohmic contact layer.

The invention discloses a method for epitaxially growing an InAs/GaSb type-II superlattice narrow-spectrum infrared photoelectric detector material. The method comprises the following steps of: selecting a substrate as a supporting body of an epitaxial layer; epitaxially growing a buffer layer on the substrate; cooling, and epitaxially growing a p-type doped InAs/GaSb type-II superlattice layer on the buffer layer; epitaxially growing an intrinsic InAs/GaSb type-II superlattice absorbing layer on the p-type doped InAs/GaSb type-II superlattice layer; epitaxially growing an n-type doped InAs/GaSb type-II superlattice layer on the intrinsic InAs/GaSb type-II superlattice absorbing layer; and epitaxially growing an n-type doped InAs cover layer on the n-type doped InAs/GaSb type-II superlattice layer to finish the epitaxial growth of the InAs/GaSb type-II superlattice narrow-spectrum infrared photoelectric detector material.

A manufacturing method for a solid-state image sensor, the method comprises the steps of: forming a charge storage region in a photoelectric converting unit by implanting a semiconductor substrate with ions of an impurity of a first conductivity type, using a first mask; heating the semiconductor substrate at a temperature of no less than 800° C. and no more than 1200° C. through RTA (Rapid Thermal Annealing); forming a surface region of the charge storage region by implanting the semiconductor substrate with ions of an impurity of a second conductivity type, using a second a mask; heating the semiconductor substrate at a temperature of no less than 800° C. and no more than 1200° C. through RTA (Rapid Thermal Annealing); and forming an antireflection film that covers the photoelectric converting unit at a temperature of less than 800° C., after the step of forming the surface region, in this order.

The invention discloses a vehicular visible light wireless digital voice communication system. The vehicular visible light wireless digital voice communication system comprises a sending module and a receiving module. The sending module comprises a digital audio acquisition unit, an RS coding unit, a PWM (pulse width modulation) unit, an LED (light emitting diode) drive unit and an LED transmitting unit, which are connected successively in circuit; the receiving module comprises a PIN photoelectric detection unit, a signal extraction unit, a PWM modulation unit, an RS decoding unit and a digital audio output unit, which are connected successively in circuit. The wireless digital voice communication system realizes instant voice communication between strange vehicles; an LED-based lamp is integrated with automobile lighting and communication without the need of an additional signal emission source installation space and occupation of scarce frequency spectrum resource. The voice signal transmission is high-speed and reliable, high in integration level, strong in anti-interference ability and low in cost, and bigger communication distance and more reliable communication are realized; moreover, a detector has high accuracy, high responsivity, low dark current, higher communication rate, stronger anti-interference ability and high reliability of a transmission channel.

Provided is a 4-transistor CMOS image in which a driving condition or a pixel structure is changed so that a transfer transistor in a pixel operates in a pinch-off condition during reset and transfer operations in order to reduce dark current and fixed-pattern noise caused by a change in an operation condition of the transfer transistor and inter-pixel characteristic discrepancy. The image sensor includes a photosensitive pixel including a transfer transistor for transferring photon-induced charges created in a photodiode; and a voltage control unit for controlling a turn-on voltage applied to a gate of the transfer transistor to be lower than a floating diffusion node voltage plus the threshold voltage of the transfer transistor during a partial or entire section of a turn-on section of the transfer transistor such that the transfer transistor operates in a pseudo pinch-off mode.

An image sensor includes one or more photodetectors for collecting charge in response to incident light and a storage region adjacent each photodetector. A transfer mechanism transfers charge from each photodetector to a respective storage region. A conductive layer or a polysilicon layer is situated over each storage region. A bias voltage terminal is connected to each conductive layer or polysilicon layer for receiving a bias voltage to bias the conductive layer or polysilicon layer to a predetermined voltage level.

This invention relates to InGaN wide spectrum solar battery with several well structures, which comprises one underlay, one transit layer, P shape InGaN layer, several quanton well structure layer, n shaoe InGaN layer, wherein, the structure layer is composed of two different InGaN alloy materials with one of thin band InxwGa1-xwN alloy to form quanton well and with second of wide gap InxbGa1-xbN alloy. The battery uses InGaN alloy materials quanton well structure to process solar energy battery absorptive area.

An imaging device includes: a semiconductor substrate; a photoelectric converting film that is forms on the semiconductor substrate and that generates charges corresponding to an incident light; a plurality of pixel portions that receive the charges from the photoelectric converting film, a floating gate that is electrically connected to the photoelectric converting film; and a transistor that fluctuates a threshold voltage so as to start to increase a drain current when an electric potential of the floating gate changes.

The invention discloses an ultraviolet light detector with a titanium dioxide nanotube array serving as a matrix and a preparation method thereof. The ultraviolet light detector comprises a titanium sheet substrate (1), the titanium dioxide nanotube array (2), an insulating layer (3) and a graphene film (4) sequentially from bottom to top, extraction electrodes (5) are arranged on the lower surface of the titanium sheet substrate (1) and the upper surface of the graphene film (4) respectively and are connected with a current measurer (6). The titanium dioxide nanotube array is prepared on the titanium sheet substrate by an anodizing method, oxygen vacancy of the array prepared by the method is less, and mismatch of stoichiometric ratio is avoided. Therefore, titanium dioxide is good in crystalline structure after annealing to lead to high response, low dark current and high ultraviolet-to-visible rejection ratio.

An unstrained InAlGaN/GaN PIN photodetector relates to a photodetector, in particular to an InAlGaN/GaN PIN photodetector which can convert light signals into electrical signals. The invention provides an unstrained InAlGaN/GaN PIN photodetector. The invention is provided with sapphire (Al2O3) substrates, a GaN buffer layer, a n-GaN layer, an i-InAlGaN photosensitive layer, a p-InAlN layer and a p-GaN top layer. The GaN buffer layer, the n-GaN layer, the i-InAlGaN photosensitive layer and the p-GaN top layer are orderly arranged on the sapphire (Al2O3) substrates from lower to top. A p-electrode is arranged on the p-GaN top layer, and a n-electrode is arranged on the n-GaN layer.

The invention belongs to the fields of photoelectric detection and image sensors, and in order to inhibit fringe field and reduce device dark current while guaranteeing a high field in the central area of the device, reference basis is provided for industrial application. The invention discloses a two-stage table-top InGaAs/InP avalanche photodiode and a preparation method thereof. The structure comprises an N<+>-InP substrate, an N-InP buffer layer, an N<->-InGaAs In0.53Ga0.47As absorbed layer, an N-InGaAsP In(1-x)GaxAsyP(1-y) component gradient layer, an N-InP charge layer, an i-InP multiplying layer, a P-InP field buffer layer and a P<+>-InP contact layer, wherein the P-InP field buffer layer forms a shallow table-top through etching, the N-InP buffer layer forms a deep table-top through etching, and constant impact ionization of photon-generated carriers inside the multiplying layer causes avalanche multiplication. The avalanche photodiode is mainly applied to the design occasionsof photoelectric detection and photoelectric sensors.

The invention discloses a solar blind ultraviolet photoelectric detector based on an amorphous gallium oxide film and a preparation method thereof, and belongs to the technical field of photoelectricdetectors. The method comprises the steps that the crystal face (0001) Al2O3 is adopted as a substrate, and the substrate is cleaned; then, the cleaned substrate is fed into a settling chamber, a radio frequency magnetic control sputtering technology is applied to the substrate to grow a gallium oxide film; finally, a hollow interdigital mask plate is used for shielding on the amorphous gallium oxide film, a direct current magnetic control sputtering method is adopted for sputtering an interdigital metal electrode on the interdigital mask plate to obtain the solar blind ultraviolet photoelectric detector, the structure is an MSM type sandwiched structure, and the Al2O3 substrate, the amorphous gallium oxide film material and the Ti/Au interdigital metal electrode are arranged from bottom to top. The manufacturing technology is simple, the repeatability is good, dark current is small, the stability is high, the response speed is high, the ultraviolet visible restrain ratio is high, andthe detector conforms to the energy-saving and emission-reducing theory, is suitable for large-scale production, and has the wide development prospect.

A device and related fabrication method is provided for an organic/inorganic hybrid optical amplifier with a function of converting infrared light to visible light. The hybrid device integrates an inorganic heterojunction phototransistor (HPT), an embedded metal electrode mirror with a dual function as an optical mirror and charge injection electrode, and an organic light emitting diode (OLED). This integrated optical amplifier is capable of amplifying the incoming light and producing light emission with a power greater than that of the incoming signal. In the second aspect of the invention, the optical amplifier is capable of detecting an incoming infrared electromagnetic wave and converting the wave back to a visible light wave. The optical device has dual functions of optical power amplification and photon energy up-conversion. The optical amplifier device consists of an InGaAs/InP based HPT structure as photodetector, gold-coated metals as embedded mirror and a top-emission OLED. New optical up-conversion imaging devices are also provided that include focal-point array of the organic/inorganic hybrid optical amplifier devices in pixelated formats. The up-conversion imaging devices have a fast response time to enable gated operation for practical applications such as night vision, active surveillance, semiconductor wafer inspection and eye-safe infrared imaging. More importantly, the up-conversion imaging devices would be particularly useful for detecting ultra-low intensity infrared scenes.

The invention discloses a method for synthetizing high-stability metal halide perovskite/lead sulfide heterostructure nanocrystals. The method comprises the following steps: firstly mixing lead halide with reactive solvent oleic acid, organic amine with long alkyl chains and octadecene in the presence of an inert gas so as to completely dissolve lead halide; then heating a mixed solution to 160-200 DEG C, rapidly injecting a caesium precursor, and reacting to generate CsPbX3; cooling to room temperature, then sequentially injecting a sulphur precursor and a lead precursor, and stirring for reaction, thereby finally obtaining the CsPbX3/PbS heterostructure nanocrystals. The synthetized CsPbX3/PbS heterostructure nanocrystals are uniform in appearance; the synthesis method is simple; due to epitaxial growth of lead sulfide, the perovskite performance stability is improved, and the CsPbX3/PbS heterostructure nanocrystals are enhanced in light-emitting efficiency and are beneficial to later-stage photoelectric device assembly.

A method to fabricate an image sensor includes providing a semiconductor substrate having a pixel region and a periphery region, forming a light sensing element on the pixel region, and forming at least one transistor in the pixel region and at least one transistor in the periphery region. The step of forming the at least one transistor in the pixel region and periphery region includes forming a gate electrode in the pixel region and periphery region, depositing a dielectric layer over the pixel region and periphery region, partially etching the dielectric layer to form sidewall spacers on the gate electrode and leaving a portion of the dielectric layer overlying the pixel region, and forming source/drain (S/D) regions by ion implantation.