Various arrangements for IC devices implementing memory with one access transistor for multiple hysteretic capacitors are disclosed. An example IC device includes a memory array of M memory units, where each memory unit includes an access transistor and N hysteretic capacitors coupled to the access transistor in a way that allows selecting all of the N hysteretic capacitors for performing READ and/or WRITEs operation when the access transistor is ON. The IC device further includes W wordlines, B bitlines, and P platelines, where N, M, W, B, and P are design variables, each being an integer greater than 1. IC devices implementing memory with one access transistor for multiple hysteretic capacitors as described herein may be used to address the scaling challenges of conventional 1T-1C memory technology and enable high density embedded memory compatible with advanced CMOS processes.

Systems and methods are described herein for dynamic random-access memory (DRAM) memory devices. In some aspects, a memory device may be constructed in a vertical orientation such that the data-lines run perpendicular to the surface of the substrate and an arbitrary number of layers may be constructed on an area, with at least some of the layers comprising an arbitrarily high density of cells. The memory device may utilize conventional capacitor cells with a refresh function, and the other usual features of activation, sensing, write-back, and selection which are common to Dennard-cell 1T1C DRAM. In some aspects, the cells may use ferroelectric capacitor dielectric resulting in devices which hold charge indefinitely without refresh, but in most other respects operate similarly to the conventional cells.

A memory device according to an embodiment includes a first conductive layer; a second conductive layer; a ferroelectric layer provided between the first conductive layer and the second conductive layer and containing hafnium oxide; a paraelectric layer provided between the first conductive layer and the ferroelectric layer and containing a first oxide; and an oxide layer provided between the paraelectric layer and the ferroelectric layer and containing a second oxide having an oxygen area density lower than an oxygen area density of the first oxide.

Methods, systems, and devices related to page policies for signal development caching in a memory device are described. In one example, a memory device in accordance with the described techniques may include a memory array, a sense amplifier array, and a signal development cache configured to store signals (e.g., cache signals, signal states) associated with logic states (e.g., memory states) that may be stored at the memory array (e.g., according to various read or write operations). The memory device may be configured to receive a read command for data stored in the memory array and transfer the data from the memory array to the signal development cache. The memory device may be configured to sense the data using an array of sense amplifiers. The memory device may be configured to write the data from the signal development cache back to the memory array based on one or more policies.

Methods, systems, and devices for cell data bulk reset are described. In some examples, a logic state (e.g., a first logic state) may be written to one or more memory cells based on an associated memory device transitioning power states. To write the first logic state to the memory cells, a first subset of digit lines may be driven to a first voltage and a plate may be driven to a second voltage. While the digit lines and plate are driven to the respective voltages, one or more word lines may be driven to the second voltage. In some instances, the word lines may be driven to the second voltage based on charge sharing occurring between adjacent word lines.

Methods, systems, and devices for memory array operation are described. A series of pulses may be applied to a fatigued memory cell to improve performance of memory cell. For example, a ferroelectric memory cell may enter a fatigue state after a number of access operations are performed at an access rate. After the number of access operations have been performed at the access rate, a fatigue state of the ferroelectric memory cell may be identified and the series of pulses may be applied to the ferroelectric capacitor at a different (e.g., higher) rate. For instance, a delay between pulses of the series of pulses may be shorter than the delay between access operations of the ferroelectric memory cell.

Methods, systems, and devices for operating a ferroelectric memory cell or cells are described. A ferroelectric memory cell may be used to store a logic state. The capacitance of a digit line of the ferroelectric memory cell may be dynamically increased prior to, and during a portion of, a read operation used to determine a stored logic state of the cell. The capacitance may be increased by leveraging intrinsic capacitance of digit lines of the array—e.g., by shorting one digit line to another digit line. Increasing the capacitance of the digit line may increase the signal on the digit line that is sensed during the read operation.

Methods, systems, and devices for operating a ferroelectric memory cell or cells are described. Before reading a memory cell, the voltage on an access line of the memory cell may be initialized to a value associated with the threshold voltage of a switching component in electronic communication with the memory cell. The voltage may be initialized by reducing the existing voltage on the access line to the value. The switching component or an additional pull down device, or both, may be used to reduce the voltage of the access line. After the access line has been initialized to the value, the read operation may be triggered.

Methods, systems, and apparatuses for redundancy in a memory array are described. A memory array may include some memory cells that are redundant to other memory cells of the array. Such redundant memory cells may be used if a another memory cell is discovered to be defective in some way; for example, after the array is fabricated and before deployment, defects in portions of the array that affect certain memory cells may be identified. Memory cells may be designated as redundant cells for numerous other memory cells of the array so that a total number of redundant cells in the array is relatively small fraction of the total number of cells of the array. A configuration of switching components may allow redundant cells to be operated in a manner that supports redundancy for numerous other cells and may limit or disturbances to neighboring cells when accessing redundancy cells.

Proposed as a configuration, a controlling method, and a testing method for a ferroelectric shadow memory are (1) a bit line non-precharge method, in which no precharging of a bit line is performed during a read/write operation; (2) a plate line charge share method, in which electric charge is shared between plate lines that are driven sequentially during store/recall operation; (3) a word line boost method, in which the potential on a word line is raised during a write operation; (4) a plate line driver boost method, in which the driving capacity of a plate line driver is raised during a store/recall operation; and (5) a testing method for detecting a defect in a ferroelectric capacitor by arbitrarily setting a potential on a bit line from outside a chip.