摘要:
A line layout structure and method in a semiconductor memory device having a hierarchical structure are provided. In a semiconductor memory device having a global word line and a local word line, and a global bit line and a local bit line, and individually disposing all of the global word line, the local word line, the global bit line and the local bit line at conductive layers among at least three layers; at least two of the global word line, the local word line, the global bit line and the local bit line are together disposed in parallel on one conductive layer. Signal lines constituting a semiconductor memory device are disposed in a hierarchical structure, whereby a semiconductor memory device advantageously having high integration, high speed and high performance may be obtained.
摘要:
A magnetic random access memory (RAM) with a multi-bit cell array structure includes an access transistor formed on a substrate, first through third resistance-variable elements, and first through third current supplying lines. The first through third resistance-variable elements are disposed between a bit line and the access transistor, and electrically connected to each other. The first through third current supplying lines are stacked alternately with the first through third resistance-variable elements. The first through third resistance-variable elements have equal resistances.
摘要:
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.
摘要:
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.
摘要:
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.
摘要:
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.
摘要:
A method of testing PRAM devices is disclosed. The method simultaneously writes input data to a plurality of memory banks by writing set data to a first group of memory banks and writing reset data to a second group of memory banks, performs a write operation test by comparing data read from the plurality of memory banks with corresponding input data, and determines a fail cell in relation to the test results.
摘要:
A writing driver circuit of a phase-change memory array which has a pulse selection circuit, a current control circuit, and a current drive circuit. The current control circuit receives a bias voltage, outputs a control signal at a second level during an enable duration of the reset pulse when the data is at a first level, and outputs a control signal at a first level during an enable duration of the set pulse when the data is at a second level. The current drive circuit outputs writing current to the phase-change memory array during the enable duration of the reset pulse or the set pulse. The writing driver circuit can select the reset pulse or the set pulse according to the logic level of the data, and control the level of current applied to the phase-change memory array according to the reset pulse or the set pulse.
摘要:
Provided are a phase-change memory device and method that maintains a resistance of a phase-change material in a reset state within a constant resistance range. In the method, data is provided to a first phase-change memory cell and then it is first determined whether data stored in the first phase-change memory cell and the data provided to the first phase-change memory cell are identical. If the data stored in the first phase-change memory cell and the data provided to the first phase-change memory cell are not identical, a complementary write current is provided to the first phase-change memory cell and it is second determined whether the data stored in the first phase-change memory cell and the data provided to the first phase-change memory cell are identical. If the data stored in the first phase-change memory cell and the data provided to the first phase-change memory cell are identical, data is provided to a second phase-change memory cell.
摘要:
Disclosed is a phase-changeable memory device and a related method of reading data. The memory device is comprised of memory cells, a high voltage circuit, a precharging circuit, a bias circuit, and a sense amplifier. Each memory cell includes a phase-changeable material and a diode connected to a bitline. The high voltage circuit provides a high voltage from a power source. The precharging circuit raises the bitline up to the high voltage after charging the bitline up to the power source voltage. The bias circuit supplies a read current to the bitline by means of the high voltage. The sense amplifier compares a voltage of the bitline with a reference voltage by means of the high voltage, and reads data from the memory cell. The memory device is able to reduce the burden on the high voltage circuit during the precharging operation, thus assuring a sufficient sensing margin during the sensing operation.