79 results about "Gain cell" patented technology

A high density horizontal merged MOS-bipolar gain memory cell is realized for DRAM operation. The gain cell includes a horizontal MOS transistor having a source region, a drain region, and a floating body region therebetween. The gain cell includes a horizontal bi-polar transistor having an emitter region, a base region and a collector region. The collector region for the horizontal bi-polar transistor serves as the floating body region for the horizontal MOS transistor. A gate opposes the floating body region and is separated therefrom by a gate oxide. The emitter region for the horizontal bi-polar transistor is coupled to a write data line.

A single transistor vertical memory gain cell with long data retention times. The memory cell is formed from a silicon carbide substrate to take advantage of the higher band gap energy of silicon carbide as compared to silicon. The silicon carbide provides much lower thermally dependent leakage currents which enables significantly longer refresh intervals. In certain applications, the cell is effectively non-volatile provided appropriate gate bias is maintained. N-type source and drain regions are provided along with a pillar vertically extending from a substrate, which are both p-type doped. A floating body region is defined in the pillar which serves as the body of an access transistor as well as a body storage capacitor. The cell provides high volumetric efficiency with corresponding high cell density as well as relatively fast read times.

A semiconductor memory element subject to a threshold voltage controlling method other than those based on low leak currents or on the implantation of impurities. Such semiconductor elements are used to form semiconductor memory elements that are employed in scaled-down structures and are conducive to high-speed write operations thanks to a sufficiently prolonged refresh cycle. These semiconductor memory elements are in turn used to constitute a semiconductor memory device. A very thin semiconductor film is used as channels so that leak currents are reduced by the quantum-mechanical containment effect in the direction of film thickness. An amount of electrical charges in each charge accumulating region is used to change conductance between a source and a drain region of each read transistor structure, the conductance change being utilized for data storage. A channel of a transistor for electrically charging or discharging each charge accumulating region is made of a semiconductor film 5 nm thick at most. The arrangement affords both high-speed data write performance and an extended data retention time. The invention provides a high-speed, power-saving semiconductor device of high integration particularly advantageous for producing a small-scale system of low-power dissipation.

A high density vertical merged MOS bipolar capacitor gain cell is realized for DRAM operation. The gain cell includes a vertical MOS transistor having a source region, a drain region, and a floating body region therebetween. The gain cell includes a vertical bi-polar transistor having an emitter region, a base region and a collector region. The base region for the vertical bi-polar transistor serves as the source region for the vertical MOS transistor. A gate opposes the floating body region and is separated therefrom by a gate oxide on a first side of the vertical MOS transistor. A floating body back gate opposes the floating body region on a second side of the vertical transistor. The base region for the vertical bi-polar transistor is coupled to a write data word line.

In a two-transistor gain cell structure, a semiconductor memory device capable of stable reading without malfunction and having small-area memory cells is provided. In a two-transistor gain cell memory having a write transistor and a read transistor, a write word line, a read word line, a write bit line, and a read bit line are separately provided, and voltages to be applied are independently set. Furthermore, a memory cell is connected to the same read word line and write bit line as those of an adjacent memory cell.

A memory architecture that utilizes single-ended dual-port destructive write memory cells and a local write-back buffer is described. Each cell has separate read and write ports that make it possible to read-out data from cells on one wordline in the array, and subsequently write-back to those cells while simultaneously reading-out the cell on another wordline in the array. By implementing an array of sense amplifiers such that one amplifier is coupled to each read bitline, and a latch receiving the result of the sensed data and delivering this data to the write data lines, it is possible to ‘pipeline’ the read-out and write-back phases of the read cycle. This allows for a write-back phase from one cycle to occur simultaneously with the read-out phase of another cycle. By extending the operation of the latch to accept data either from the sense amplifier, or from the memory data inputs, modified by the column address and masking bits, it is also possible to pipeline the read-out and the modify-write-back phases of a write cycle, allowing them to occur simultaneously. The architecture preferably employs a nondestructive read memory cell such as 2T or 3T gain cells, achieving an SRAM-like cycle and access times with a smaller and more SER immune memory cell.

A vertical gain memory cell including an n-channel metal-oxide semiconductor field-effect transistor (MOSFET) and p-channel junction field-effect transistor (JFET) transistors formed in a vertical pillar of semiconductor material is provided. The body portion of the p-channel transistor is coupled to a second source/drain region of the MOSFET which serves as the gate for the JFET. The second source/drain region of the MOSFET is additionally coupled to a charge storage node. Together the second source/drain region and charge storage node provide a bias to the body of the JFET that varies as a function of the data stored by the memory cell. A non destructive read operation is achieved. The stored charge is sensed indirectly in that the stored charge modulates the conductivity of the JFET so that the JFET has a first turn-on threshold for a stored logic “1” condition and a second turn-on threshold for a stored logic “0” condition. The charge storage node is a plate capacitor which surrounds the second source/drain region of the MOSFET. The vertical gain cell is fabricated so that the write word line, read bit line, read word line and capacitor are buried beneath the silicon surface. As a result the cell can be fabricated in an area as small as four (4) lithographic feature squares.

A single transistor vertical memory gain cell with long data retention times. The memory cell is formed from a silicon carbide substrate to take advantage of the higher band gap energy of silicon carbide as compared to silicon. The silicon carbide provides much lower thermally dependent leakage currents which enables significantly longer refresh intervals. In certain applications, the cell is effectively non-volatile provided appropriate gate bias is maintained. N-type source and drain regions are provided along with a pillar vertically extending from a substrate, which are both p-type doped. A floating body region is defined in the pillar which serves as the body of an access transistor as well as a body storage capacitor. The cell provides high volumetric efficiency with corresponding high cell density as well as relatively fast read times.

A memory cell includes: a charge storage element (e.g., capacitor); a switch constructed and arranged to selectively connect the charge storage element to a first data line, responsive to a first select signal; and a gain element having an input connected to receive a signal from the capacitor and constructed and arranged to selectively provide a corresponding output signal to a second data line, responsive to a second select signal. The switch can be a FET having a drain connected to the first data line, a source connected to the capacitor and a gate connected to the first select signal. The gain element can be a FET having a gate connected to the capacitor, a source connected to the second data line and a drain selectively connected to one of an upper power supply and a lower power supply. The switch can transfer a signal from the first data line onto the capacitor and can transfer a signal from the capacitor onto the first data line when selected by the first select signal. A two-dimensional array of such memory cells can be formed, wherein the first select signal and the second select signal orthogonally select cells, to facilitate matrix pivot operations and bit interleave/de-interleave operations. Also, a method of addressing an array of such memory cells can comprise: writing groups of bits linearly arrayed with respect to each other; and reading groups of bits linearly arrayed with respect to each other and orthogonally disposed to the groups of bits written.

A highly integrated gain cell-type semiconductor memory is provided. A first insulator, a read bit line, a second insulator, a third insulator, a first semiconductor film, first conductive layers, and the like are formed. A projecting insulator is formed thereover. Then, second semiconductor films and a second gate insulating film are formed to cover the projecting insulator. After that, a conductive film is formed and subjected to anisotropic etching, so that write word lines are formed on side surfaces of the projecting insulator. A third contact plug for connection to a write bit line is formed over a top of the projecting insulator. With such a structure, the area of the memory cell can be 4 F² at a minimum.

A high density vertical single transistor gain cell is realized for DRAM operation. The gain cell includes a vertical transistor having a source region, a drain region, and a floating body region therebetween. A gate opposes the floating body region and is separated therefrom by a gate oxide on a first side of the vertical transistor. A floating body back gate opposes the floating body region on a second side of the vertical transistor and is separated therefrom by a dielectric to form a body capacitor.

T-coil structures are used in one embodiment to inject programmably-variable amounts of transistor biasing currents into the respective drains of current sinking transistor means of a broadband differential amplifier such that, when the differential amplifier is in common mode, total transistor drain current will exceed total voltage-dropping current passing through corresponding voltage-dropping resistances of the amplifier's transistor means. The T-coil structures keep the parasitic capacitances of the programmable current sources that provide the bias currents de-lumped from capacitances of the amplifier's output nodes and/or capacitances of the amplifier's voltage-dropping resistances (variable resistances) to thereby maintain a wide bandwidth.

A laser device is provided for generating an ultraviolet output. The device comprises a laser having at least one diode-pumped alkali metal vapor gain cell for generating a near infrared laser output, and at least two optically-nonlinear crystals. In one particular embodiment, the laser uses a Rb gas cell and generates radiation at a wavelength of about 199 nm and at least 200 mW of power with a linewidth of less than 10 GHz. In another embodiment, narrow linewidth UV light is generated at 265 nm.

To achieve a stable reading operation in a memory cell having a gain-cell structure, a write transistor is configured, which has a source and a drain that are formed on the insulating layer, a channel formed on the insulating layer and between the source and the drain and made of a semiconductor, and a gate formed on an upper portion of the insulating layer and between the source and the drain and electrically insulated from the channel by a gate insulating film and controlling the potential of the channel. The channel electrically connects the source and the drain on the side surfaces of the source and the drain.

A multi-port memory architecture utilizing an open bitline configuration for the read bitline is described. The memory is sub-divided into two arrays (A and B) consisting of memory gain cells arranged in a matrix formation, the cells having two general ports or separate read and write ports to enable simultaneous a read and write operation. Each memory array includes a reference wordline coupled to reference cells. When the reference cell is accessed, the read bitline (RBL) discharges to a level at half the value taken by a cell storing a 0 or 1. Each pair of RBLB in the same column of the two arrays is coupled to a differential sense amplifier, and each write bitline (WBL) in the two arrays is linked to write drivers WBLs in the two arrays are driven to the same voltage and at the same slew rate. The WBL swing in each array creates coupling noise by the bitline-to-bitline capacitors. For a given sense amplifier and its associated RBLs, the coupling creates an identical coupling noise on RBLA and RBLB that are positioned in the two arrays A and B. This common mode noise is rejected by the differential sense amplifier. Thus, a read sense amplifier can accurately discriminate between the signal by activating the cell by way of RWL, and the reference cell by way of REFWL.

A DRAM memory cell and process sequence for fabricating a dense (20 or 18 square) layout is fabricated with silicon-on-insulator (SOI) CMOS technology. Specifically, the present invention provides a dense, high-performance SRAM cell replacement that is compatible with existing SOI CMOS technologies. Various gain cell layouts are known in the art. The present invention improves on the state of the art by providing a dense layout that is fabricated with SOI CMOS. In general terms, the memory cell includes a first transistor provided with a gate, a source, and a drain respectively; a second transistor having a first gate, a second gate, a source, and a drain respectively; and a capacitor having a first terminal, wherein the first terminal of said capacitor and the second gate of said second transistor comprise a single entity.