Unity Semiconductor Corporation

Hefei Reliance Memory Limited

Steve Kuo-Ren Hsia

Darrell Rinerson

Steven W Longcor

Christophe J Chevallier

Wayne I Kinney

Edmond R Ward

John Espinoza Sanchez, Jr

Philip Swab

Philip F S Swab

John Sanchez

Emond Ward

A re-writeable non-volatile memory device including a re-writeable non-volatile two-terminal memory element (ME) having tantalum. The ME including a first terminal, a second terminal, a first layer of a conductive metal oxide (CMO), and a second layer in direct contact with the first layer. The second layer and the first layer being operative to store at least one-bit of data as a plurality of resistive states, and the first and second layer are electrically in series with each other and with the first and second terminals.

Memory element with a reactive metal layer

A memory cell including conductive oxide electrodes is disclosed. The memory cell includes a memory element operative to store data as a plurality of resistive states. The memory element includes a layer of a conductive metal oxide (CMO) (e.g., a perovskite) in contact with an electrode that may comprise one or more layers of material. At least one of those layers of material can be a conductive oxide (e.g., a perovskite such as LaSrCoO-LSCoO or LaNiO-LNO) that is in contact with the CMO. The conductive oxide layer can be selected as a seed layer operative to provide a good lattice match with and/or a lower crystallization temperature for the CMO. The conductive oxide layer may also be in contact with a metal layer (e.g., Pt). The memory cell additionally exhibits non-linear IV characteristics, which can be favorable in certain arrays, such as non-volatile two-terminal cross-point memory arrays.

A memory cell including conductive oxide electrodes is disclosed. The memory cell includes a memory element operative to store data as a plurality of resistive states. The memory element includes a layer of a conductive metal oxide (CMO) (e.g., a perovskite) in contact with an electrode that may comprise one or more layers of material. At least one of those layers of material can be a conductive oxide (e.g., a perovskite such as LaSrCoO&#x2014;LSCoO or LaNiO&#x2014;LNO) that is in contact with the CMO. The conductive oxide layer can be selected as a seed layer operative to provide a good lattice match with and/or a lower crystallization temperature for the CMO. The conductive oxide layer may also be in contact with a metal layer (e.g., Pt). The memory cell additionally exhibits non-linear IV characteristics, which can be favorable in certain arrays, such as non-volatile two-terminal cross-point memory arrays.

A treated conductive element is provided. A conductive element can be treated by depositing either a reactive metal or a very thin layer of material on the conductive element. The reactive metal (or very thin layer of material) would typically be sandwiched between the conductive element and an electrode. The structure additionally exhibits non-linear IV characteristics, which can be favorable in certain arrays.

Method for fabricating multi-resistive state memory devices

Multi-resistive state memory device with conductive oxide electrodes

A memory cell including a memory element and a non-ohmic device (NOD) that are electrically in series with each other is disclosed. The NOD comprises a semiconductor based selection device operative to electrically isolate the memory element from a range of voltages applied across the memory cell that are not read voltages operative read stored data from the memory element or write voltages operative to write data to the memory element. The selection device may comprise a pair of diodes that are electrically in series with each other and disposed in a back-to-back configuration. The memory cell may be fabricated over a substrate (e.g., a silicon wafer) that includes active circuitry. The selection device and the semiconductor materials (e.g., poly-silicon) that form the selection device are fabricated above the substrate and are integrated with other thin film layers of material that form the memory cell.

Selection device for re-writable memory

A multi-layer non-volatile memory integrally formed on top of a substrate including active circuitry is disclosed. Each layer of memory includes memory cells (e.g., a two-terminal memory cell) having a multi-resistive state material layer that changes its resistive state between a low resistive state and a high resistive state upon application of a write voltage across the memory cell. Data stored in the memory cells can be non-destructively determined by applying a read voltage across the memory cells. Data storage capacity can be tailored to a specific application by increasing or decreasing the number of memory layers that are integrally fabricated on top of the substrate (e.g., more than four layers or less than four layers). The memory cells can include a non-ohmic device for allowing access to the memory cell only during read and write operations. Each memory layer can comprise a cross point array.

Four vertically stacked memory layers in a non-volatile re-writeable memory device

A conductive memory stack is provided. The memory stack includes a bottom electrode, a top electrode and a multi-resistive state element. The multi-resistive state element is sandwiched between the electrodes such that the top face of the bottom electrode is in contact with the multi-resistive state element's bottom face and the bottom face of the top electrode is in contact with the multi-resistive state element's top face. The bottom electrode, the top electrode and the multi-resistive state element all have sides that are adjacent to their faces. Furthermore, the sides are at least partially covered by a sidewall layer.

Conductive memory stack with sidewall

A conductive memory stack is provided. The memory stack includes a bottom electrode, a top electrode and a multi-resistive state element that is sandwiched between the electrodes. The bottom electrode can be described as having a top face with a first surface area, the top electrode has a bottom face with a second surface area and the multi-resistive state element has a bottom face with a third surface area and a top face with a fourth surface area. The multi-resistive state element's bottom face is in contact with the bottom electrode's top face and the multi-resistive state element's top face is in contact with the top electrode's bottom face. Furthermore, the fourth surface area is not equal to the second surface area.

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San Jose, CA, United States of America

Steve Kuo-Ren Hsia