Methods, systems, and devices for a modified write voltage for memory devices are described. In an example, the memory device may determine a first set of memory cells to be switched from a first logic state (e.g., a SET state) to a second logic state (e.g., a RESET state) based on a received write command. The memory device may perform a read operation to determine a subset of the first set of memory cells (e.g., a second set of memory cells) having a conductance threshold satisfying a criteria based on a predicted drift of the memory cells. The memory device may apply a RESET pulse to each of the memory cells within the first set of memory cells, where the RESET pulse applied to the second set of memory cells is modified to decrease voltage threshold drift in the RESET state.

Disclosed herein are related to a system and a method of extending a lifetime of a memory cell. In one aspect, a memory controller applies a first pulse having a first amplitude to the memory cell to write input data to the memory cell. In one aspect, the memory controller applies a second pulse having a second amplitude larger than the first amplitude to the memory cell to extend a lifetime of the memory cell. The memory cell may include a resistive memory device or a phase change random access memory device. In one aspect, the memory controller applies the second pulse to the memory cell to repair the memory cell in response to determining that the memory cell has failed. In one aspect, the memory controller periodically applies the second pulse to the memory cell to extend the lifetime of the memory cell before the memory cell fails.

A control method to operate a memory device, a control method to operate a memory system and a control system are provided. The control method includes providing a first voltage to a memory device for accessing a memory element of the memory device; obtaining an aging information of the memory device; and providing a second voltage to the memory device according to the aging information, wherein the first voltage and the second voltage are reverse biased voltages.

Methods, systems, and devices for dirty write on power off are described. In an example, the described techniques may include writing memory cells of a device according to one or more parameters (e.g., reset current amplitude), where each memory cell is associated with a storage element storing a value based on a material property associated with the storage element. Additionally, the described techniques may include identifying, after writing the memory cells, an indication of power down for the device and refreshing, before the power down of the device, a portion of the memory cells based on identifying the indication of the power down for the device. In some cases, refreshing includes modifying at least one of the one or more parameters for a write operation for the portion of the memory cells.

A read technique for both SLC (single level cell) and MLC (multi-level cell) cross-point memory can mitigate drift-related errors with minimal or no drift tracking. In one example, a read at a higher magnitude voltage is applied first, which causes the drift for cells in a lower threshold voltage state to be reset. In one example, the read at the first voltage can be a full float read to minimize disturb. A second read can then be performed at a lower voltage without the need to adjust the read voltage due to drift.

Crossbar arrays with reduced disturbance and methods for programming the same are disclosed. In some implementations, an apparatus comprises: a plurality of rows; a plurality of first columns; a plurality of second columns; a plurality of devices. Each of the plurality of devices is connected among one of the plurality of rows, one of the plurality of first columns, and one of the plurality of second columns. The device further comprises a shared end on the plurality of first columns or the plurality of the second columns connecting to the plurality of the devices in the same row or column; the shared end is grounding or holds a stable voltage potential. In some implementations, one of the devices is: a RRAM, a floating date, a phase change device, an SRAM, a memristor, or a device with tunable resistance. In some implementations the stable voltage potential is a constant DC voltage.

A method is disclosed that includes causing a first set of a plurality of voltage pulses to be applied to memory cells of a memory device, a voltage pulse of the first set of the voltage pulses placing the memory cells of the memory device at a voltage level associated with a defined voltage state. The method also includes determining a set of bit error rates associated with the memory cells of the memory device in view of a data mapping pattern for the memory cells of the memory device, wherein the data mapping pattern assigns a voltage level associated with a reset state to at least a portion of the memory cells of the memory device. The method further includes determining whether to apply one or more second sets of the voltage pulses to the memory cells of the memory device in view of a comparison between the set of bit error rates for the memory cells and a previously measured set of bit error rates for the memory cells.

According to one embodiment, a memory device includes a first wiring line, a second wiring line, a memory cell connected between the first and second wiring lines, including a resistance change memory element having first and second resistance states, and a two-terminal switching element connected in series to the resistance change memory element, and a voltage application circuit which applies a write voltage signal having a first polarity and setting a desired resistance state to the resistance change memory element, to the memory cell, and applies, after the write voltage signal is applied to the memory cell, a second polarity voltage signal having a magnitude that prevents the two-terminal switching element from being set to the on-state, to the memory cell.

A standard potential used for reading is set flexibly according to the state of a storage device. A data memory cell group stores data. A reference memory cell group stores a plurality of reference potentials. A standard potential generating section selects a prescribed number of reference potentials from among the plurality of reference potentials stored in the reference memory cell group and generates the standard potential. A reference potential selection control section controls the selection by the standard potential generating section according to prescribed conditions. A sense amplifier amplifies data read out from the data memory cell group, by using the standard potential as a standard.

The present disclosure provides a memory device, which includes a plurality of electrically bipolar variable memory devices and a storage transistor. The electrically bipolar variable memory devices are electrically connected to a plurality of word lines respectively, the storage transistor is electrically connected to the electrically bipolar variable memory devices, where one end of each of the electrically bipolar variable memory devices is electrically connected to a corresponding one of the word lines, and another end of each of the electrically bipolar variable memory devices is electrically connected to the gate of the storage transistor.