摘要:
A CCD structure wherein the patterned well implant and/or patterned barrier implant geometries are modified to exploit two dimensional potential modification effects to induce potential gradation along the length of the CCD pixel. Preferably these geometry modifications are in the form of wedge-shaped extensions of the well doping into the barrier region. The modifications thus induced to the potential profile for electrons in the direction of the charge transfer along the CCD pixel mean that the regions of flat potential, wherein carrier transport is diffusion dominated, are shortened, so that charge transfer efficiency can be improved at reasonably high clock rates.
摘要:
An image sensor array (12) is comprised of a plurality of sensor elements (60) arranged in rows (62) and columns (64). Each element (60) is operable to modulate an output voltage signal responsive to charge accumulating in its gate region (70) responsive to incident light. Circuitry (74, 84, 78, 72) is provided to obtain and store a signal that is related to a threshold voltage differential produced by the accumulated charge, and not to the intrinsic threshold voltages or sizes of sensors (60). The array (12) has automatic blooming control, and can exhibit electronic iris, zooming and panning functions.
摘要:
A low 1/f noise amplifier has been provided for an output of a CCD imager. To reduce clock noise, the amplifier employs a differential detection scheme. Linear stages (54, 76) are coupled by capacitors (60, 82) to a differential amplifier (64). Differential amplifier (64) employs a first (112, 118) and a second (172, 198) differential transistor pair. The second differential pair (172, 198) is cross-coupled to the outputs of the first differential pair (112, 118) by load resistances (180, 206) with the voltage drop across them remaining substantially constant. To maintain stability, the positive and negative branches of the amplifier are periodically reset by a resetter (210). The input nodes (62, 86) are periodically reset to a voltage reference.
摘要:
The specification discloses a charge transfer imaging device (10) having a charge removal gate (26). Pulses (30) of sufficient amplitude and frequency are applied to gate (26) in order to remove charge from device (10) by electron-hole recombination through interface traps of electrons and holes. Pulses of one amplitude reduce blooming of the device when used as an imager, while pulses of a second amplitude may be used to produce imager aperture control and gamma correction. Further, the charge removal technique may be used to control charge injection device (96) operation.
摘要:
Gates of individual devices on a slice are connected through a resistance to the device substrate, and through the same resistance to other device gates. This interconnection and high-resistance drain gives the gate protection from static charge buildup and subsequent catastrophic discharge which would result in a faulty device. This method protects each gate from the time of deposition to final device packaging.
摘要:
This specification discloses a CCD imager which includes a line addressing circuit (24) which selectively addresses CCD imaging gates (48). Output signals are clocked under the gates (48) to a buffer register (30) which is constructed in the form of a tree. Signals from under each of the CCD gates (48) travel an identical length path through the buffer register (30) to a charge detection circuit (46) measured by the number of pixels involved. The output signals thus take the same time, or same number of clock pulses, to travel the length of the buffer register (30) to enable all line switching to be accomplished during the horizontal blanking time of a television thus eliminating the switching noise from the television screen.
摘要:
A uniphase, buried-channel, semiconductor charge transfer device wherein a portion of each cell includes an inversion layer, or "virtual electrode" at the semiconductor surface, shielding that region from any gate-induced change in potential. Each cell is comprised of four regions (I, II, III, IV) wherein the characteristic impurity profile of each region determines the maximum potential generated therein for the gate "on" and gate "off" conditions. Clocking the gate causes the potential maxima in regions I and II to cycle above and below the fixed potential maxima in regions III and IV beneath the virtual electrode. Directionality of charge transfer is thereby achieved, since the potential maximum for region II (.phi..sub.max II) remains greater than for region I (.phi..sub.max I) and .phi..sub.max IV>.phi..sub.max III, for both gate conditions. A self-aligned process for fabrication is provided, including a number of ion implant stages to fix the required impurity profiles in each cell for generating the correct potential profiles for charge propagation. CCD imagers, memory devices, an analog processors are contemplated systems wherein the invention is to be implemented.
摘要:
A transparent conductive layer of SnO.sub.2 is deposited on a substrate by an RF-plasma assisted chemical vapor reaction of CO.sub.2 with an organic tin compound, such as tetramethyl tin, for example. A CCD optical imager is fabricated, using the method of the invention to form a transparent conductive layer thereon.
摘要:
A fluidtight, hermetically sealed, miniature transducer adapted to be inserted into the human body and useful for directly monitoring internal fluid or pneumatic pressures within the human body is disclosed. Semiconductor strain gauge elements constituting a piezoresistive bridge are formed by diffusion on the surface of one side of an integral flexible, rectangular, silicon diaphragm area of a single crystal silicon base. A single crystal silicon cover is eutectically bonded to the base by a metallic laminate seal. The base, cover, and seal define an evacuated fluidtight chamber containing the strain gauge elements. Electrical conductors, which include diffused conductor paths under an insulating oxide layer, extend from the piezoresistive bridge to contact pads outside the fluidtight chamber. The contact pads can be connected to a readout device for electrically measuring the pressure differential between the evacuated chamber and fluid external to the transducer as a function of time.
摘要:
A pixel of an image sensor includes only two signal lines per pixel, a pinned photodiode for sensing light, a floating base bipolar transistor, and no reset and address transistors. The floating base bipolar transistor provides the pixel with a gain, which can increase pixel sensitivity and reduce noise. The pixel also incorporates a vertical blooming control structure for an efficient blooming suppression. The output terminals of the pixel are coupled to a common column output line terminated by a special current sensing correlated double sampling circuit, which is used for subtraction of emitter leakage current. Based on this structure, the pixel has high sensitivity, high response uniformity, low noise, reduced size, and efficient layout.