Systems, methods and apparatus to program a memory cell to have a threshold voltage to a level representative of one value among more than two predetermined values. A first voltage pulse is driven across the memory cell to cause a predetermined current to go through the memory cell. The first voltage pulse is sufficient to program the memory cell to a level representative of a first value. To program the memory cell to a level representative of a second value, a second voltage pulse, different from the first voltage pulse, is driven across the memory cell within a time period of residual poling in the memory cell caused by the first voltage pulse.

An array device and a writing method thereof are provided. A synapse array device includes: a crossbar array, in which a resistive memory element is connected to each intersection of a plurality of row lines and a plurality of column lines; a row select/drive circuit selecting a row line of the crossbar array and applying a pulse signal to the selected row line; a column select/drive circuit selecting a column line of the crossbar array and applying a pulse signal to the selected column line; and a writing part writing to the resistive memory element connected to the selected row line and the selected column line. A first write voltage with controlled pulse width is applied to the selected row line, and a second write voltage with controlled pulse width is applied to the selected column line to perform set writing of the resistive memory element.

A variable resistive memory device includes a memory cell, a first current-applying block, a second current-applying block and a mode setting circuit. The memory cell includes a first electrode, a second electrode, and a memory layer, the memory layer interposed between the first electrode and the second electrode. The first current-applying block is configured to flow a first current to the first electrode that flows from the first electrode to the second electrode. The second current-applying block is configured to flow a second current to the second electrode that flows from the second electrode to the first electrode. The mode setting circuit is configured to selectively provide any one of the first electrode of the first current-applying block and the second electrode of the second current-applying block with a first voltage. When the memory cell is selected, the selected current-applying block, among the first current-applying block and the second current-applying block, is driven. When the first current-applying block is selected, a second voltage is applied to the second electrode. When the second current-applying block is selected, the second voltage is applied to the first electrode. The first voltage has a voltage level by a threshold voltage higher than the second voltage.

An integrated circuit memory device, having: a first wire; a second wire; a memory cell connected between the first wire and the second wire; a first voltage driver connected to the first wire; and a second voltage driver connected to the second wire. During an operation to read the memory cell, the second voltage driver is configured to start ramping up a voltage applied on the second wire after the first voltage driver starts ramping up and holding a voltage applied on the first wire.

A ferroelectric component includes a first electrode, a tunnel barrier layer disposed on the first electrode to include a ferroelectric material, a tunneling control layer disposed on the tunnel barrier layer to control a tunneling width of electric charges passing through the tunnel barrier layer, and a second electrode disposed on the tunneling control layer.

Provided is a variable resistance random-access memory for suppressing degradation of performance by recovering a memory cell that fails. A variable resistance random-access memory of the disclosure includes a memory array, a row selection circuit, a column selection circuit, a controller, an error checking and correcting (ECC) circuit, an error bit flag register, and an error bit address register. The memory array includes a plurality of memory cells. The column selection circuit includes a sense amplifier and a write driver/read bias circuit. The error bit flag register stores bits for indicating presence/absence of an error bit in a write operation. The error bit address register stores an address of the error bit. The controller recovers the error bit when a predetermined event occurs.

Disclosed herein is a memory cell. The memory cell may act both as a combined selector device and memory element. The memory cell may be programmed by applying write pulses having different polarities. Different polarities of the write pulses may program different logic states into the memory cell. The memory cell may be read by read pulses all having the same polarity. The logic state of the memory cell may be detected by observing different threshold voltages when the read pulses are applied. The different threshold voltages may be responsive to the different polarities of the write pulses.

Methods, systems, and devices for programming techniques for polarity-based memory cells are described. A memory device may use a first type of write operation to program one or more memory cells to a first state and a second type of write operation to program one or more memory cells to a second state. Additionally or alternatively, a memory device may first attempt to use the first type of write operation to program one or more memory cells, and then may use the second type of write operation if the first attempt is unsuccessful.

A variable resistance memory device includes: a memory cell including a first and second sub memory cell; and a first, second and third conductor. The first sub memory cell is above the first conductor, and includes a first variable resistance element and a first bidirectional switching element. The second sub memory cell is above the second conductor, and includes a second variable resistance element and a second bidirectional switching element. The second conductor is above the first sub memory cell. The third conductor is above the second sub memory cell. The variable resistance memory device is configured to receive first data and to write the first data to the memory cell when the first data does not match second data read from the memory cell.

Memory devices have an array of elements in two or more dimensions. The memory devices use multiple access lines arranged in a grid to access the memory devices. Memory cells are located at intersections of the access lines in the grid. Drivers are used for each access line and configured to transmit a corresponding signal to respective memory cells of the plurality of memory cells via a corresponding access line. The memory devices also include compensation circuitry configured to determine which driving access lines driving a target memory cell of the plurality of memory cells has the most distance between the target memory cell and a respective driver. The plurality of access lines comprise the driving access lines. The compensation circuitry also is configured to output compensation values to adjust the voltages of the driving access lines based on a polarity of the voltage of the longer driving access line.