Abstract: A nonvolatile memory device includes multiple first bit lines extending in a first direction, multiple word lines formed on the first bit lines and extending in a second direction different from the first direction, and multiple second bit lines, formed on the word lines and extending in the first direction. The nonvoliative memory device also includes multiple twin memory cells, each of which includes a first memory cell coupled between a first bit line and a word line and a second memory cell coupled between the word line and a second bit line. The first and second memory cells store different data.

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: 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 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: 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 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: 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: 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 semiconductor memory device and a layout structure of word line contacts, in which the semiconductor memory device includes an active region, a plurality of memory cells, and word line contacts. The active region is disposed in a first direction as a length direction on a semiconductor substrate and is used as a word line. The plurality of memory cells are disposed in the first direction on the active region and are each constructed of one variable resistance device and one diode device. In the word line contacts, at least one each is disposed between respective units, wherein each unit is constructed of predetermined numbers of memory cells on the active region. A bridge effect, such as a short-circuit between adjacent word lines, can be prevented or substantially reduced.

Abstract: A PRAM and programming method are disclosed. The PRAM includes a memory cell array including a test cell, a write driver applying a program pulse and providing a program current to the memory cell array, a sense amplification and verification circuit reading data programmed in the memory cell array and performing a program verify operation on the data, and a program loop control unit storing program verification result for the test cell at each program loop during test operation and generating the program pulse according to the program verification result to control the start of the program loop during normal operation.

Abstract: A semiconductor memory device, which has an array of memory cells connected with a plurality of bit line pairs and a plurality of word lines, to perform a read or write operation of data, having low power consumption is provided. The device includes a first power supply for supplying a first power source voltage. Also, a second power supply supplies a second power source voltage having a lower voltage level than the first power source voltage. Further, the device includes a standard ground. An elevated ground circuit provides an elevated ground voltage having a higher voltage level than that of the standard ground. A first power circuit is connected with the first power supply and the standard ground, and operates in response to the first power source voltage. A second power circuit is connected with the second power supply and the elevated ground circuit, and operates in response to the second power source voltage. Thereby, power and chip size can be reduced.

Abstract: A semiconductor memory device, which has an array of memory cells connected with a plurality of bit line pairs and a plurality of word lines, to perform a read or write operation of data, having low power consumption is provided. The device includes a first power supply for supplying a first power source voltage. Also, a second power supply supplies a second power source voltage having a lower voltage level than the first power source voltage. Further, the device includes a standard ground. An elevated ground circuit provides an elevated ground voltage having a higher voltage level than that of the standard ground. A first power circuit is connected with the first power supply and the standard ground, and operates in response to the first power source voltage. A second power circuit is connected with the second power supply and the elevated ground circuit, and operates in response to the second power source voltage. Thereby, power and chip size can be reduced.