Abstract: Phase change memory devices having cell diodes and related methods are provided, where the phase change memory devices include a semiconductor substrate of a first conductivity type and a plurality of parallel word lines disposed on the semiconductor substrate, the word lines have a second conductivity type different from the first conductivity type and have substantially flat top surfaces, a plurality of first semiconductor patterns are one-dimensionally arrayed on each word line along a length direction of the word line, the first semiconductor patterns have the first conductivity type or the second conductivity type, second semiconductor patterns having the first conductivity type are stacked on the first semiconductor patterns, an insulating layer is provided on the substrate having the second semiconductor patterns, the insulating layer fills gap regions between the word lines, gap regions between the first semiconductor patterns and gap regions between the second semiconductor patterns, a plurality of p

Abstract: Embodiments of the invention provide a multi-layer semiconductor memory device and a related error checking and correction (ECC) method. The multi-layer semiconductor memory device includes first and second memory cell array layers, wherein the first memory cell array layer stores first payload data. The multi-layer semiconductor memory device also includes an ECC engine selectively connected to the second memory cell array layer and configured to receive the first payload data, generate first parity data corresponding to the first payload data, and store the first parity data exclusively in the second memory cell array layer.

Abstract: A nonvolatile memory device includes a stack-type memory cell array, a selection circuit and a read circuit. The memory cell array includes multiple memory cell layers and a reference cell layer, which are vertically laminated. Each of the memory cell layers includes multiple nonvolatile memory cells for storing data, and the reference cell layer includes multiple reference cells for storing reference data. The selection circuit selects a nonvolatile memory cell from the memory cell layers and at least one reference cell, corresponding to the selected nonvolatile memory cell, from the reference cell layer. The read circuit supplies a read bias to the selected nonvolatile memory cell and the selected reference cell corresponding to the selected nonvolatile memory cell, and reads data from the selected nonvolatile memory cell.

Abstract: The present invention provides a nonvolatile memory device that uses a resistance material. The nonvolatile memory device includes: a stacked memory cell array having a plurality of memory cell layers stacked in a vertical direction, the stacked memory cell array having at least one memory cell group and at least one redundancy memory cell group; and a repair control circuit coupled to the stacked memory cell array, the repair control circuit configured to repair a defective one of the at least one memory cell group with a selected one of the at least one redundancy memory cell group. The features that enable repair improve the fabrication yield of the nonvolatile memory device.

Abstract: A resistance semiconductor memory device of a three-dimensional stack structure, and a word line decoding method thereof, are provided.

Abstract: A resistance random access memory (RRAM) having a source line shared structure and an associated data access method. The RRAM, in which a write operation of writing data of first state and second state to a selected memory cell is performed through first and second write paths having mutually opposite directions, includes word lines, bit lines, a memory cell array and a plurality of source lines. The memory cell array includes a plurality of memory cells each constructed of an access transistor coupled to a resistive memory device. The memory cells are disposed in a matrix of rows and columns and located at each intersection of a word line and a bit line. Each of the plurality of source lines is disposed between a pair of word lines and in the same direction as the word lines. A positive voltage is applied to a source line in a memory cell write operation.

Abstract: A memory cell of a resistive semiconductor memory device, a resistive semiconductor memory device having a three-dimensional stack structure, and related methods are provided. The memory cell of a resistive semiconductor memory device includes a twin cell, wherein the twin cell stores data values representing one bit of data. The twin cell includes a main unit cell connected to a main bit line and a word line, and a sub unit cell connected to a sub bit line and the word line. Also, the main unit cell includes a first variable resistor and a first diode, and the sub unit cell includes a second variable resistor and a second diode.

Abstract: A non-volatile memory device is employed in which data values are determined by the polarities at both ends of a cell, The non-volatile memory device includes a first decoder which decodes a plurality of predetermined bit values of a row address into a first address and is disposed in a row direction of a memory cell array; a second decoder which decodes the other bit values of the row address into a second address and is disposed in a column direction of the memory cell array; and a driver which applies bias voltages to a word line which corresponds to the first address or the second address in accordance with the data values. By including first and second decoders and decoding a row address in two steps, a bi-directional RRAM according to the present invention can perform addressing at high speeds while reducing chip size.

Abstract: A method of biasing a memory cell array during a data writing operation and a semiconductor memory device, in which the semiconductor memory device includes: a memory cell array including a plurality of memory cells in which a first terminal of a memory cell is connected to a corresponding first line among a plurality of first lines and a second terminal of a memory cell is connected to a corresponding second line among a plurality of second lines; and a bias circuit for biasing a selected second line to a first voltage and non-selected second lines to a second voltage.

Abstract: A non-volatile memory device, in which data values are determined by polarities at cell terminals, includes a memory cell array. The memory cell array is divided into multiple sub cell arrays, each sub cell array including at least one input/output line and an X-decoder/driver. First input/output lines included in different sub cell arrays may be simultaneously activated and bias voltages may be applied to the activated first input/output lines in accordance with the data values. The non-volatile memory device may be a bi-directional resistive random access memory (RRAM).

Abstract: An integrated circuit memory device includes an array of nonvolatile memory cells (e.g., variable resistance cells) having a first plurality of lines electrically coupled to memory cells therein. A read/write control circuit is provided. The read/write control circuit includes a read/write merge circuit and a column selection circuit. The read/write control circuit, which is configured to drive a selected one of the first plurality of lines with unequal write and read voltages during respective write and read operations, includes a compensating unit. This compensating unit is configured to provide a read compensation current to the selected one of the first plurality of lines circuit during the read operation.

Abstract: A non-volatile memory device includes a memory cell array including a memory cell array having word lines, bit lines, and non-volatile memory cells, each non-volatile memory cell having a variable resistive material and an access element connected between the corresponding word line and the corresponding bit line. The variable resistive material has a resistance level that varies according to data to be stored. A selection circuit selects at least one non-volatile memory cell in which data will be written. An adaptive write circuit/method supplies a write bias to the selected non-volatile memory cell through the bit line connected to the selected non-volatile memory cell to write data in the selected non-volatile memory cell and varies (e.g., increases) the write bias until the resistance level of the selected non-volatile memory cell varies.

Abstract: A semiconductor memory device of one aspect includes a memory cell block including n global word lines, and corresponding m sub word lines for each of the n global word lines, where n and m are natural numbers. The memory device further includes a plurality of word line driving circuits which respectively control a voltage of the sub word lines according to a logic level of each corresponding global word line and inputted address signals, and a plurality of control circuits which transmit the address signals to the word line driving circuits or interrupt transmission of the address signals according to the logic level of the global word line. Each of the word line driving circuits includes a first transistor which maintains the voltage of the respective sub word line at a first voltage and a second transistor which maintains the voltage of the sub word line at the first voltage or a second voltage.

Abstract: There is provided a resistive memory device, the device including: a plurality of word lines and a plurality of bit lines arranged such that the word lines intersect the bit lines; a plurality of resistive memory cells each having a variable resistive material coupled between the corresponding word line and the corresponding bit line and an access element; selecting circuits selecting one of the plurality of resistive memory cells; and a filament-forming circuit supplying a filament-forming voltage to the selected resistive memory cell through the bit line coupled to the selected resistive memory cell while increasing the filament-forming voltage from a predetermined voltage level until filaments having a predetermined thickness are formed in the variable resistive material of the selected resistive memory cell.

Abstract: A semiconductor memory device includes a plurality of cell array layers including a plurality of word lines extending in a first direction, a plurality of bit lines extending in a second direction that intersects the first direction, and a plurality of memory cells disposed at intersections of the word lines and the bit lines. Each of the word lines has a word line position, each of the bit lines has a bit line position, and each of the memory cells includes a variable resistance device in series with a diode. The cell array layers are arranged in layers in a third direction that is perpendicular to the first and second directions. The bit lines of each of the cell array layers having a same bit line position are connected to a common column selector transistor, or the word lines of the cell array layers having a same word line position are connected to a common word line driver.

Abstract: A resistive memory device is provided. The resistive memory device includes word lines arranged in M rows, bit lines arranged in N columns, local source lines arranged in M/2 rows, and resistive memory cells arranged in M rows and N columns. Each of the resistive memory cells includes a resistance variable element having a first electrode connected to a corresponding bit line, and a cell transistor having a first terminal connected to a second electrode of the resistance variable element, a second terminal connected to a corresponding local source line, and a control terminal connected to a corresponding word line. The local source line is commonly connected to the second terminals of the cell transistors of the two neighboring rows.

Abstract: Embodiments of the invention provide devices or methods that include a status bit representing an inversion of stored data. New data is written to selected cells, the new data is selectively inverted, and the status bit is selectively toggled, based on a comparison between pre-existing data and new data associated with a write command. A benefit of embodiments of the invention is that fewer memory cells must be activated in many instances (when compared to conventional art approaches). Moreover, embodiments of the invention may also reduce the average amount of activation current required to write to variable resistive memory devices and other memory device types.

Abstract: A phase change random access memory on aspect includes a memory cell array block including a plurality of phase change memory cells, a column decoder, a row decoder, a column selector, and a write driver. The memory further includes a write boosting unit having a plurality of internal charge pumps which boost a first voltage to generate a write driving voltage which drives the write driver, where the number of internal charge pumps that are activated during a write operation is varied according to a number of phase change memory cells which are selected during the write operation. The memory still further includes a column boosting unit which boosts the first voltage to generate a column driving voltage which drives the column decoder, and a row boosting unit which boosts the first voltage to generate a row driving voltage which drives the row decoder.

Abstract: In various methods of performing program operations in phase change memory devices, selected memory cells are repeatedly programmed to obtain resistance distributions having desired characteristics such as adequate sensing margins.

Abstract: A method of performing a program-suspend-read operation in a PRAM device comprises programming a write block comprising N unit program blocks in response to a program operation request, and suspending the program operation after programming M unit program blocks, where M is less than N, in response to a read operation request. The method further comprises executing the requested read operation, and then resuming the programming of the write data block and programming (N?M) remaining unit program blocks.