Methods, systems, and devices supporting a socket design for a memory device are described. A die may include one or more memory arrays, which each may include any number of word lines and any number of bit lines. The word lines and the bit lines may be oriented in different directions, and memory cells may be located at the intersections of word lines and bit lines. Sockets may couple the word lines and bit lines to associated drivers, and the sockets may be located such that memory cells farther from a corresponding word line socket are nearer a corresponding bit line socket, and vice versa. For example, sockets may be disposed in rows or regions that are parallel to one another, and which may be non-orthogonal to the corresponding word lines and bit lines.

Methods, systems, and devices for memory cell selection to enable a memory device to select a targeted memory cell during a write operation are described. The memory device may apply a first pulse to a selected bit line of the targeted memory cell while applying a voltage to deselected word lines to prevent current leakage. If the targeted memory is not selected after the first pulse, the memory device may apply a second pulse to the selected bit line while applying a voltage to the deselected word lines. If the targeted memory cell is not selected following the second pulse, the memory device may apply a third pulse to the selected bit line while applying the voltage to the deselected word lines. The memory device may detect a snapback event after any of the pulses if the targeted memory cell is selected.

A semiconductor memory may include: variable resistance layers and insulating layers alternately stacked; conductive pillars passing through the variable resistance layers and the insulating layers; a slit insulating layer passing through the insulating layers and extending in a first direction; and conductive layers interposed between the slit insulating layer and the variable resistance layers. The variable resistance layers may remain in an amorphous state during a program operation.

A memory device including a three dimensional crosspoint memory array comprising memory cells assigned to a plurality of groups, wherein each group is associated with a respective at least one program pulse parameter based on programming responses of memory cells of that group; and access circuitry to program a memory cell of a first group of the plurality of groups to a first program state by applying a program pulse having the at least one program pulse parameter associated with the first group.

A memory device including a memory array comprising a plurality of memory cells, respective memory cells each comprising a storage element comprising phase change memory programmable to three unique states; and a controller comprising circuitry, the controller to convert binary data into ternary data at a ratio of three bits of binary data to two trits of ternary data and provide the ternary data to the memory array for storage.

Methods, systems, and devices for memory cells for storing operational data are described. A memory device may include an array of memory cells with different sets of cells for storing data. A first set of memory cells may store data for operating the memory device, and the associated memory cells may each contain a chalcogenide storage element. A second set of memory cells may store host data. Some memory cells included in the first set may be programmed to store a first logic state and other memory cells in the first set may be left unprogrammed (and may represent a second logic state). Sense circuitry may be coupled with the array and may determine a value of data stored by the first set of memory cells.

Systems, methods, and apparatus related to spike current suppression in a memory array. In one approach, a memory device includes a memory array having a cross-point memory architecture. The memory array has access lines (e.g., word lines and/or bit lines) configured to access memory cells of the memory array. Each access line has left and right portions. Spike current suppression is implemented by charge screening structures. The charge screening structures are formed by laterally integrating insulating layers into selected interior regions of the left and/or right portions of the access line. The insulating layers vertically separate the access line into top and bottom conductive portions above and below the insulating layers. For memory cells located overlying or underlying the insulating layers, the resistance to each memory cell is increased because the cell is accessed using only the higher resistance path of the top or bottom conductive portion. During a spike discharge, charge is choked by this higher resistance path. This suppresses spike current that occurs when the memory cell is selected.

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.

The present disclosure includes apparatuses, methods, and systems for three-state programming of memory cells. An embodiment includes a memory having a plurality of memory cells, and circuitry configured to program a memory cell of the plurality of memory cells to one of three possible data states by applying a voltage pulse to the memory cell, determining whether the memory cell snaps back in response to the applied voltage pulse, and applying an additional voltage pulse to the memory cell based on the determination of whether the memory cell snaps back.

The present disclosure includes apparatuses and methods for programming memory cells using asymmetric current pulses. An embodiment includes a memory having a plurality of self-selecting memory cells, and circuitry configured to program a self-selecting memory cell of the memory by applying a first current pulse or a second current pulse to the self-selecting memory cell, wherein the first current pulse is applied for a longer amount of time than the second current pulse and the first current pulse has a lower amplitude than the second current pulse.