G11C11/2255

Memory cell with a ferroelectric capacitor integrated with a transtor gate

Described herein are ferroelectric (FE) memory cells that include transistors having gates with FE capacitors integrated therein. An example memory cell includes a transistor having a semiconductor channel material, a gate dielectric over the semiconductor material, a first conductor material over the gate dielectric, a FE material over the first conductor material, and a second conductor material over the FE material. The first and second conductor materials form, respectively, first and second capacitor electrodes of a capacitor, where the first and second capacitor electrodes are separated by the FE material (hence, a “FE capacitor”). Separating a FE material from a semiconductor channel material of a transistor with a layer of a gate dielectric and a layer of a first conductor material eliminates the FE-semiconductor interface that may cause endurance issues in some other FE memory cells.

Memory array decoding and interconnects

Methods and apparatuses for thin film transistors and related fabrication techniques are described. The thin film transistors may access two or more decks of memory cells disposed in a cross-point architecture. The fabrication techniques may use one or more patterns of vias formed at a top layer of a composite stack, which may facilitate building the thin film transistors within the composite stack while using a reduced number of processing steps. Different configurations of the thin film transistors may be built using the fabrication techniques by utilizing different groups of the vias. Further, circuits and components of a memory device (e.g., decoder circuitry, interconnects between aspects of one or more memory arrays) may be constructed using the thin film transistors as described herein along with related via-based fabrication techniques.

Low voltage ferroelectric memory cell sensing
11501816 · 2022-11-15 · ·

Methods, systems, and devices for low voltage ferroelectric memory cell sensing are described. As part of an access operation for a memory cell, gates of two cascodes may be biased to compensate for associated threshold voltages. An extracted signal corresponding to a charge stored in the memory cell may be transferred through a first cascode to charge a first capacitor. Similarly, a reference signal developed at a dummy digit line may be transferred through a second cascode to charge a second capacitor. By comparing the reference signal developed at the dummy digit line to the extracted signal from the memory cell, the effect of variations in memory cell performance on the sense window may be reduced. Additionally, based on biasing the gates of the cascodes, the difference between the signals compared at the sense component may be low compared to other sensing schemes.

Thin film transistor deck selection in a memory device
11502091 · 2022-11-15 · ·

Methods, systems, and devices for thin film transistor deck selection in a memory device are described. A memory device may include memory arrays arranged in a stack of decks formed over a substrate, and deck selection components distributed among the layers to leverage common substrate-based circuitry. For example, each memory array of the stack may include a set of digit lines of a corresponding deck, and deck selection circuitry operable to couple the set of digit lines with a column decoder that is shared among multiple decks. To access memory cells of a selected memory array on one deck, the deck selection circuitry corresponding to the memory array may each be activated, while the deck selection circuitry corresponding to a non-selected memory array on another deck may be deactivated. The deck selection circuitry, such as transistors, may leverage thin-film manufacturing techniques, such as various techniques for forming vertical transistors.

Memory Array Including Dummy Regions

3D memory arrays including dummy conductive lines and methods of forming the same are disclosed. In an embodiment, a memory array includes a ferroelectric (FE) material over a semiconductor substrate, the FE material including vertical sidewalls in contact with a word line; an oxide semiconductor (OS) layer over the FE material, the OS layer contacting a source line and a bit line, the FE material being between the OS layer and the word line; a transistor including a portion of the FE material, a portion of the word line, a portion of the OS layer, a portion of the source line, and a portion of the bit line; and a first dummy word line between the transistor and the semiconductor substrate, the FE material further including first tapered sidewalls in contact with the first dummy word line.

THREE-DIMENSIONAL MEMORY
20220359569 · 2022-11-10 ·

Three-dimensional memories are provided. A three-dimensional memory includes a memory cell array, a first interconnect structure, a bit line decoder and a second interconnect structure. The bit line decoder is formed under the memory cell array and the first interconnect structure. The memory cell array includes a plurality of memory cells formed in a plurality of levels stacked in a first direction. The first interconnect structure includes at least one bit line extending in a second direction that is perpendicular to the first direction. The bit line includes a plurality of sub-bit lines stacked in the first direction. Each of the sub-bit lines is coupled to the memory cells that are arranged in a line in the corresponding level of the memory cell array. The second interconnect structure is configured to connect the bit line to the bit line decoder passing through the first interconnect structure.

FERROELECTRIC RANDOM ACCESS MEMORY (FRAM) DEVICES WITH ENHANCED CAPACITOR ARCHITECTURE

Embodiments of the disclosure are directed to advanced integrated circuit structure fabrication and, in particular, to ferroelectric random access memory (FRAM) devices with an enhanced capacitor architecture. Other embodiments may be disclosed or claimed.

MEMORY CIRCUIT, MEMORY DEVICE AND OPERATION METHOD THEREOF
20220352300 · 2022-11-03 ·

The present disclosure provides a memory circuit, a memory device and an operating method of the memory device. The memory device includes a storage transistor, a variable capacitance device and a control transistor. The variable capacitance device is electrically connected to the gate of the storage transistor, and the control transistor is connected to the storage transistor in series.

Deck selection layouts in a memory device
11616068 · 2023-03-28 · ·

Methods, systems, and devices for deck selection layouts in a memory device are described. In some implementations, a tile of a memory array may be associated with a level above a substrate, and may include a set of memory cells, a set of digit lines, and a set of word lines. Selection transistors associated with a tile of memory cells may be operable for coupling digit lines of the tile with circuitry outside the tile, and may be activated by various configurations of one or more access lines, where the various configurations may be implemented to trade off or otherwise support design and performance characteristics such as power consumption, layout complexity, operational complexity, and other characteristics. Such techniques may be implemented for other aspects of tile operations, including memory cell shunting or equalization, tile selection using transistors of a different level, or signal development, or various combinations thereof.

EMBEDDED FERROELECTRIC MEMORY CELL
20220351769 · 2022-11-03 ·

The present disclosure relates to an integrated chip structure. The integrated chip structure includes a first source/drain region and a second source/drain region disposed within a substrate. A select gate is disposed over the substrate between the first source/drain region and the second source/drain region. A ferroelectric random-access memory (FeRAM) device is disposed over the substrate between the select gate and the first source/drain region. A first sidewall spacer, including one or more dielectric materials, is arranged laterally between the select gate and the FeRAM device. An inter-level dielectric (ILD) structure laterally surrounds the FeRAM device and the select gate and vertically overlies a top surface of the first sidewall spacer.