11283 results about "Bit line" patented technology

When programming a contiguous page of memory storage units, every time a memory storage unit has reached its targeted state and is program-inhibited or locked out from further programming, it creates a perturbation on an adjacent memory storage unit still under programming. The present invention provides as part of a programming circuit and method in which an offset to the perturbation is added to the adjacent memory storage unit still under programming. The offset is added as voltage offset to a bit line of a storage unit under programming. The voltage offset is a predetermined function of whether none or one or both of its neighbors are in a mode that creates perturbation, such as in a program inhibit mode. In this way, an error inherent in programming in parallel high-density memory storage units is eliminated or minimized.

A DRAM-like non-volatile memory array includes a cell array of non-volatile cell units with a DRAM-like cross-coupled latch-type sense amplifier. Each non-volatile cell unit has two non-volatile cell devices with respective bit lines and source lines running in parallel and laid out perpendicular to the word line associated with the non-volatile cell unit. The two non-volatile cell devices are programmed with erased and programmed threshold voltages as a pair for storing a single bit of binary data. The two bit lines of each non-volatile cell unit are coupled through a Y-decoder and a latch device to the two respective inputs of the latch-type sense amplifier which provides a large sensing margin for the cell array to operate properly even with a narrowed threshold voltage gap. Each non-volatile cell device may be a 2 T FLOTOX-based EEPROM cell, a 2 T flash cell, 11 T flash cell or a 1.5 T split-gate flash cell.

In an embodiment of the present invention, a hierarchical differential sensing approach is effectuated wherein an array of 1T DRAM cells are organized in rows and columns in which the rows represent words and the columns represent bits of the word, each bit column having more than one pair of balanced, true and complement local bit lines, the local bit lines being connected to a pair of balanced, true and complement global bit lines by way of CMOS transistor switches.

The present invention efficiently decides line failure and contact failure in a semiconductor device. The semiconductor device has a plurality of bit line groups in which connection with local I / O lines is controlled by the same column selection signal line. A failure detecting circuit compares a first data group read from a first bit line group and a second data group read from a second bit line group to detect whether or not connection failure (contact failure) with the column selection signal line occurs in one of the first and second bit line groups.

It is important to ensure good selectivity of a single magnetic tunnel junction storage cell within a memory array without affecting nearby storage cells. For this purpose, this memory array of storage cells preferably comprises a) an array of electrically conducting bit lines and electrically conducting word lines which form intersections therebetween, b) a storage cell disposed at each of said intersections, each storage cell comprising at least one reversible magnetic region or layer characterized by a magnetization state which can be reversed by applying thereto a selected external magnetic field, said reversible magnetic layer comprising a material whose magnetization state is more easily reversed upon a change in the temperature thereof, and c) a temperature change generator for changing the temperature of said reversible magnetic layer of only a selected one of said array of storage cells at any moment. To select a cell, it is preferable to select a cell by using a brief pulse of tunnelling current between the intersecting bit and word lines at that cell in order to provide sufficient Joule heating to facilitate a change in the magnetization state of its reversible magnetic layer, which preferably comprises a ferrimagnetic material.

A semiconductor memory device includes a first cell array including a plurality of unit cells and a bit line sense amplifying unit for sensing and amplifying data signals stored in the unit cells. Each unit cell is provided with a PMOS transistor and a capacitor. Therefore, the semiconductor memory device efficiently operates with low voltage without any degradation of operation speed.

A method for manufacturing a memory device having a plurality of memory cells. Each memory cell has a non-volatile resistive memory element with a small active area. A plurality of memory cells are formed at selected locations of at least a portion of a semiconductor wafer. To form the memory cells, a lower electrode layer and a memory material layer are deposited over at least a portion of the wafer. Patterns are formed over desired contact locations of the memory material layer and etching is used to remove portions of the memory material layer. The etching step undercuts the patterns and forms memory elements having a protruding contact portion with an apex contact area. The pattern is removed, and an upper electrode is formed and electrically coupled to the contact area. Corresponding access devices and word / bit line conductor grids are provided and coupled to the memory cells.

A sense amplifier circuit senses and amplifies a signal read from memory cells arranged at intersections of word-lines and bit-lines. A write circuit reads first data held in a first memory cell of the memory cells, and writes second data corresponding to the first data in a second memory cell different from the first memory cell. A data latch circuit holds data read from the first memory cell. A logic operation circuit performs a logic operation using data read from the second memory cell and data held in the data latch circuit as input values and outputs third data as an operation value. A write-back circuit writes the third data back to the first memory cell.

A data path circuit of a semiconductor memory device includes: a bit line sense amplifier driven by a first power supply voltage; a local input / output line sense amplifier; a column selecting unit operatively connecting a pair of bit lines connected to the bit line sense amplifier and a pair of local input / output lines connected to the local input / output line sense amplifier in response to a column selection signal; and a local input / output line precharge unit precharging the pair of local input / output lines with a second power supply voltage different from the first power supply voltage during a period for which the column selection signal is in an inactive state.

A memory includes a plurality of memory cells each including a true data input connected to a true bit line and complementary data input connected to a complementary bit line, and two inverters connected head-to-tail firstly to the true data input and secondly to the complementary data input. The memory also includes a test circuit includes a plurality of test cells, each test cell includes a true data input connected to a complementary data input of the preceding test cell and a complementary data input connected to the true data input of the following test cell, the complementary data input of the last test cell being connected to the true data input of the first test cell, each test cell comprising a first inverter connected between the true data input and the complementary data input. The looped chain thus formed propagates a signal whose period is a function of the performance of the storage cells.

A method of forming a self-aligned contact structure with a locally etched conductive layer comprises the steps of: preparing a substrate formed with gate structures comprising a first conductive layer, a second conductive layer, and an insulating layer; depositing a photoresist material layer on the substrate; performing a lithographic step with a bit-line contact node photomask or a bit-line contact photomask to expose a portion of the surface of the substrate; etching the exposed second conductive layer with an etchant; removing the remaining photoresist material layer; forming a sidewall spacer on the sidewalls of each gate structure; forming a dielectric layer to cover the substrate; and performing lithographic and etching steps to remove the dielectric layer and to form self-aligned contact structure.

A fast low voltage ballistic program, ultra-short channel, ultra-high density, dual-bit multi-level flash memory is described with a two or three polysilicon split gate side wall process. The structure and operation of this invention is enabled by a twin MONOS cell structure having an ultra-short control gate channel of less than 40nm, with ballistic injection which provides high electron injection efficiency and very fast program at low program voltages of 3~5V. The cell structure is realized by (i) placing side wall control gates over a composite of Oxide-Nitride-Oxide (ONO) on both sides of the word gate, and (ii) forming the control gates and bit diffusion by self-alignment and sharing the control gates and bit diffusions between memory cells for high density. Key elements used in this process are: 1) Disposable side wall process to fabricate the ultra short channel and the side wall control gate with or without a step structure, and 2) Self-aligned definition of the control gate over the storage nitride and the bit line diffusion, which also runs in the same direction as the control gate. The features of fast program, low voltage, ultra-high density, dual-bit, multi-level MONOS NVRAM of the present invention include: 1) Electron memory storage in nitride regions within an ONO layer underlying the control gates, 2) high density dual-bit cell in which there are two nitride memory storage elements per cell, 3) high density dual-bit cell can store multi-levels in each of the nitride regions, 4) low current program controlled by the word gate and control gate, 5) fast, low voltage program by ballistic injection utilizing the controllable ultra-short channel MONOS, and 6) side wall control poly gates to program and read multi-levels while masking out memory storage state effects of the unselected adjacent nitride regions and memory cells. The ballistic MONOS memory cell is arranged in the following array: each memory cell contains two nitride regions for one word gate, and ½ a source diffusion and ½ a bit diffusion. Control gates can be defined separately or shared together over the same diffusion. Diffusions are shared between cells and run in parallel to the side wall control gates, and perpendicular to the word line.

A memory array having memory cells comprising a diode and a phase change material is reliably programmed by maintaining all unselected memory cells in a reverse biased state. Thus leakage is low and assurance is high that no unselected memory cells are disturbed. In order to avoid disturbing unselected memory cells during sequential writing, previously selected word and bit lines are brought to their unselected voltages before new bit lines and word lines are selected. A modified current mirror structure controls state switching of the phase change material.

Methods of forming electrically conductive and / or semiconductive features for use in integrated circuits are disclosed. Various pattern transfer and etching steps can be used, in combination with pitch-reduction techniques, to create densely-packed features. The features can have a reduced pitch in one direction and a wider pitch in another direction. Conventional photo-lithography steps can be used in combination with pitch-reduction techniques to form elongate, pitch-reduced features such as bit-line contacts, for example.

A semiconductor memory device may have a DRAM cell mode and a non-volatile memory cell mode without a capacitor, including multiple transistors arranged in an array and having floating bodies, word lines connected to gate electrodes of the transistors, bit lines at a first side of the gate electrodes connected to drains of the transistors, source lines at a second side of the gate electrodes, different from the first side, and connected to sources of the transistors on the semiconductor substrate, and charge storage regions between the gate electrodes and the floating bodies.

A method and system for providing and utilizing a magnetic memory are described. The magnetic memory includes a plurality of magnetic storage cells. Each magnetic storage cell includes magnetic element(s) programmable due to spin transfer when a write current is passed through the magnetic element(s) and selection device(s). The method and system include driving a first current in proximity to but not through the magnetic element(s) of a portion of the magnetic storage cells. The first current generates a magnetic field. The method and system also include driving a second current through the magnetic element(s) of the portion of the magnetic storage cells. The first and second currents are preferably both driven through bit line(s) coupled with the magnetic element(s). The first and second currents are turned on at a start time. The second current and the magnetic field are sufficient to program the magnetic element(s).

In a preferred integrated circuit embodiment, a write-once memory array includes at least one test bit line which provides a respective test memory cell at the far end of each respective word line relative to its word line driver, and further includes at least one test word line which provides a respective test memory cell at the far end of each respective bit line relative to its bit line driver. An intra-layer short between word lines may be detected, such as during manufacturing testing, by biasing adjacent word lines to different voltages and detecting whether any leakage current flowing from one to another exceeds that normally accounted for by the memory cells and other known circuits. Intra-layer bit line shorts and inter-layer word line and bit line shorts may also be similarly detected. An "open" in a word line or bit line may be detected by trying to program the test memory cell at the far end of each such word line or bit line. If successfully programmed, the continuity of each word line and bit line is assured, and the programming circuitry for each word line and bit line is also known to be functional.

A silicon on insulator (SOI) dynamic random access memory (DRAM) cell and array and method of manufacture. The memory cell includes a trench storage capacitor connected by a self aligned buried strap to a vertical access transistor. A buried oxide layer isolates an SOI layer from a silicon substrate. The trench capacitor is formed in the substrate and the access transistor is formed on a sidewall of the SOI layer. A polysilicon strap connected to the polysilicon plate of the storage capacitor provides a self-aligned contact to the source of the access transistor. Initially, the buried oxide layer is formed in the wafer. Deep trenches are etched, initially just through the SOI layer and the BOX layer. Protective sidewalls are formed in the trenches. Then, the deep trenches are etched into the substrate. The volume in the substrate is expanded to form a bottle shaped trench. A polysilicon capacitor plate is formed in the deep trenches and conductive polysilicon straps are formed in the trenches between the capacitor plates and the SOI sidewalls. Device regions are defined in the wafer and a sidewall gate is formed in the deep trenches. Shallow trenches isolation (STI) is used to isolate and define cells. Bitlines and wordlines are formed on the wafer.

In an organic memory which is included in a radio chip formed from a thin film, data are written to the organic memory by a signal inputted with a wired connection, and the data is read with a signal by radio transmission. A bit line and a word line which form the organic memory are each selected by a signal which specifies an address generated based on the signal inputted with a wired connection. A voltage is applied to a selected memory element. Thus writing is performed. Reading is performed by a clock signal or the like which are generated from a radio signal.

The process for programming a set of memory cells is improved by adapting the programming process based on behavior of the memory cells. For example, a set of program pulses is applied to the word line for a set of flash memory cells. A determination is made as to which memory cells are easier to program and which memory cells are harder to program. Bit line voltages (or other parameters) can be adjusted based on the determination of which memory cells are easier to program and which memory cells are harder to program. The programming process will then continue with the adjusted bit line voltages (or other parameters).

A capacitor memory is realized, wherein a capacitor stores data and a diode controls to store data “1” or “0”. Diode has four terminals wherein first terminal serves as word line, second terminal serves as storage node, third terminal is floating, and fourth terminal serves as bit line, wherein back channel effect is suppressed adding additional ions in the bottom side of third terminal or applying negative voltage in the well or substrate. A capacitor plate couples to second terminal, which plate has no coupling region to first, third and fourth terminal. With no coupling, the inversion layer of plate in the storage node is isolated from the adjacent nodes. In doing so, the plate can swing ground level to positive supply level to write. As a result, no negative generator is required for controlling plate. Word line and bit line keep ground level during standby, and rise to supply level for read or write operation. In this manner, no holding current is required during standby, and operating current is dramatically reduced with no negative generator. Write has a sequence to clear the state of cell before writing to store data regardless of previous state. Refresh cycle is periodically asserted to sustain data. The present invention can be applied for destructive read, or for nondestructive read adding pull-down device to bit line. The height of cell is almost same as control circuit on the bulk or SOI wafer.

An fast program, ultra-high density, dual-bit, multi-level flash memory process, which can be applied to a ballistic step split gate side wall transistor, or to a ballistic planar split gate side wall transistor, which enables program operation by low voltage requirement on the floating gate during program is described. Two side wall floating gates are paired with a single word line select gate, and word lines are arranged to be perpendicular both the bit lines and control gate lines. Two adjacent memory cells on the same word line do not require an isolation region. Also, the isolation region between adjacent memory cells sharing the same bitline is defined by the minimum lithography feature, utilizing a self align fill technique. Adjacent memory cells on the same word line share bitline diffusion as well as a third poly control gate. Control gates allow program and read access to the individual floating gate. In addition to the dual-bit nature of the cell, density can be even further improved by multi-level storage. In one embodiment, the dual multi-level structure is applied to the ballistic step split gate side wall transistor. In a second embodiment, the dual multi-level structure is applied to the ballistic planar split gate side wall transistor. Both types of ballistic transistors provide fast, low voltage programming. The control gates are used to override or suppress the various threshold voltages on associated floating gates, in order to program to and read from individual floating gates. The targets for this non-volatile memory array are to provide the capabilities of high speed, low voltage programming (band width) and high density storage.