A memory device includes a multi-layer stack, a plurality of channel layers and a plurality of ferroelectric layers. The multi-layer stack is disposed on a substrate and includes a plurality of gate layers and a plurality of dielectric layers stacked alternately. The plurality of channel layers penetrate through the multi-layer stack and are laterally spaced apart from each other, wherein the plurality of channel layers include a first channel layer and a second channel layer, and a first electron mobility of the first channel layer is different from a second electron mobility of the second channel layer. Each of the plurality of channel layers are spaced apart from the multi-layer stack by one of the plurality of ferroelectric layers, respectively.

Some embodiments include a capacitor having a container-shaped bottom portion. The bottom portion has a first region over a second region. The first region is thinner than the second region. The first region is a leaker region and the second region is a bottom electrode region. The bottom portion has an interior surface that extends along the first and second regions. An insulative material extends into the container shape. The insulative material lines the interior surface of the container shape. A conductive plug extends into the container shape and is adjacent the insulative material. A conductive structure extends across the conductive plug, the insulative material and the first region of the bottom portion. The conductive structure directly contacts the insulative material and the first region of the bottom portion, and is electrically coupled with the conductive plug. Some embodiments include methods of forming assemblies.

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.

An antiferroelectric memory device includes at least one antiferroelectric memory cell. Each of the at least one antiferroelectric memory cell includes a first electrode, a second electrode and a stack containing an antiferroelectric layer and a doped semiconductor layer or a ferroelectric layer located between the first and the second electrodes.

A memory cell includes a transistor over a semiconductor substrate. The transistor includes a ferroelectric layer arranged along a sidewall of a word line. The ferroelectric layer includes a species with valence of 5, valence of 7, or a combination thereof. An oxide semiconductor layer is electrically coupled to a source line and a bit line. The ferroelectric layer is disposed between the oxide semiconductor layer and the word line.

A method (of reading a ferroelectric field-effect transistor (FeFET) configured as a 2-bit storage device that stores two bits, wherein the FeFET includes a first source/drain (S/D) terminal, a second S/D terminal, a gate terminal and a ferroelectric layer, a second bit being at a first end of the ferroelectric layer, the first end being proximal to the first S/D terminal) includes reading the second bit including: applying a gate sub-threshold voltage to the gate terminal; applying a read voltage to the second S/D terminal; applying a do-not-disturb voltage to the first S/D terminal; and sensing a first current at the second S/D terminal; and wherein the read voltage is lower than the do-not-disturb voltage.

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.

A memory device includes: a first layer stack and a second layer stack formed successively over a substrate, where each of the first and the second layer stacks includes a first metal layer, a second metal layer, and a first dielectric material between the first and the second metal layers; a second dielectric material between the first and the second layer stacks; a gate electrode extending through the first and the second layer stacks, and through the second dielectric material; a ferroelectric material extending along and contacting a sidewall of the gate electrode; and a channel material, where a first portion and a second portion of the channel material extend along and contact a first sidewall of the first layer stack and a second sidewall of the second layer stack, respectively, where the first portion and the second portion of the channel material are separated from each other.

Some embodiments include ferroelectric assemblies. Some embodiments include a capacitor which has ferroelectric insulative material between a first electrode and a second electrode. The capacitor also has a metal oxide between the second electrode and the ferroelectric insulative material. The metal oxide has a thickness of less than or equal to about 30 Å. Some embodiments include a method of forming an assembly. A first capacitor electrode is formed over a semiconductor-containing base. Ferroelectric insulative material is formed over the first electrode. A metal-containing material is formed over the ferroelectric insulative material. The metal-containing material is oxidized to form a metal oxide from the metal-containing material. A second electrode is formed over the metal oxide.

A semiconductor device includes a plurality of magnetic tunnel junction (MTJ) structures in an interlayer insulating layer on a substrate. A blocking layer is on the interlayer insulating layer and the plurality of MTJ structures. An upper insulating layer is on the blocking layer. An upper interconnection is on the upper insulating layer. An upper plug is connected to the upper interconnection and a corresponding one of the plurality of MTJ structures and extends into the upper insulating layer and the blocking layer. The blocking layer includes a material having a higher absorbance constant than the upper insulating layer.