Seagate Technology Incorporated

Honeywell International Inc.

Daniel Seymour Reed

Yong Lu

Hai Li

Yiran Chen

Harry Hongyue Liu

Romney R Katti

Rod V Bowman

Andrew John Carter

Gordon Alan Shaw

Dimitar Velikov Dimitrov

Song Sheng Xue

Paul E Anderson

Lonny L Berg

Owen J Hynes

Daniel Baseman

Wei D Z Zou

Hongyue Liu

Paul S Fechner

David W Zou

Yon Lu

Roy R Wang

Hassan Kaakani

Paul Anderson

Various embodiments of the present invention are generally directed to a method and apparatus for providing different bit set modes for a resistive sense memory (RSM) array, such as a spin-torque transfer random access memory (STRAM) or resistive random access memory (RRAM) array. In accordance with some embodiments, a group of RSM cells in a non-volatile semiconductor memory array is identified for application of a bit set operation. A bit set value is selected from a plurality of bit set values each separately writable to the RSM cells to place said cells in a selected resistive state. The selected bit set value is thereafter written to at least a portion of the RSM cells in the identified group.

Bit set modes for a resistive sense memory cell array

A non-volatile memory cell and associated method of use. In accordance with some embodiments, the memory cell includes a transistor comprising source and drain regions spanned by a gate region, and a resistive sense element (RSE) connected to the drain region of the transistor. The RSE is programmed to a first resistance by flowing a first write current through the RSE and then through the drain and source regions of the transistor. The RSE is programmed to a second resistance by flowing a second write current through the drain region and then through the RSE, the second write current bypassing the source region.

Non-volatile memory cell with resistive sense element block erase and uni-directional write

Various embodiments are generally directed to a method and apparatus associated with operating a first memory device with multiple interfaces and a status register. In some embodiments, a first interface is engaged by a host. A memory device that has a plurality of memory cells comprised of at least a magnetic tunneling junction and a spin polarizing magnetic material is connected to a second interface. A status register is maintained by logging at least an error or busy signal during data transfer operations through the first and second interfaces.

Computer memory device with multiple interfaces

Method and apparatus for using a uni-directional write current to store different logic states in a non-volatile memory cell, such as a modified STRAM cell. In some embodiments, the memory cell has an unpinned ferromagnetic reference layer adjacent a cladded conductor, a ferromagnetic storage layer and a tunneling barrier between the reference layer and the storage layer. Passage of a current along the cladded conductor induces a selected magnetic orientation in the reference layer, which is transferred through the tunneling barrier for storage by the storage layer. Further, the orientation of the applying step is provided by a cladding layer adjacent a conductor along which a current is passed and the current induces a magnetic field in the cladding layer of the selected magnetic orientation.

Spin-torque bit cell with unpinned reference layer and unidirectional write current

Method and apparatus for operating a memory device with a status register. In some embodiments, the memory device has a plurality of individually programmable non-volatile memory cells comprised of at least a resistive sense memory. The memory device engages an interface and maintains a status register in some embodiments by logging at least an error or busy signal during data transfer operations.

Computer memory device with status register

Apparatus and associated method for transferring data to memory, such as resistive sense memory (RSM). In accordance with some embodiments, input data comprising a sequence of logical states are transferred to a block of memory by concurrently writing a first logical state from the sequence to each of a first plurality of unit cells during a first write step, and concurrently writing a second logical state from the sequence to each of a second non-overlapping plurality of unit cells during a second write step.

Multi-stage parallel data transfer

Various embodiments of the present invention are generally directed to a method and apparatus for carrying out a partial block update operation upon a resistive sense memory (RSM) array, such as formed from STRAM or RRAM cells. The RSM array is arranged into multi-cell blocks (sectors), each block having a physical block address (PBA). A first set of user data is written to a selected block at a first PBA. A partial block update operation is performed by writing a second set of user data to a second block at a second PBA, the second set of user data updating a portion of the first set of user data in the first PBA. The first and second blocks are thereafter read to retrieve the second set of user data and a remaining portion of the first set of user data.

Resistive sense memory array with partial block update capability

Method and apparatus are disclosed for storing data to non-volatile resistive sense memory (RSM) memory cells of a semiconductor memory array, including but not limited to resistive random access memory (RRAM) and spin-torque transfer random access memory (STTRAM or STRAM) cells. In accordance with various embodiments, a plurality of addressable data blocks from a host device are stored in a buffer. At least a portion of each of the addressable data blocks are serially transferred to a separate register of a plurality of registers. The transferred portions of said addressable data blocks are thereafter simultaneously transferred from the registers to selected RSM cells of the array.

Simultaneously writing multiple addressable blocks of user data to a resistive sense memory cell array

In accordance with various embodiments, a column of non-volatile memory cells is connected between opposing first and second control lines. A fixed reference voltage is applied to the second control line. The memory cells are simultaneously programmed to a first resistive state by applying a first voltage to the first control line that is greater than the fixed reference voltage. Less than all of the memory cells are subsequently simultaneously programmed to a different, second resistive state by applying a second voltage to the first control line that is less than the fixed reference voltage, so that at the conclusion of the respective programming steps a first portion of the memory cells along said column are at the first resistive state and a second portion of the memory cells along said column are at the second resistive state.

Non-volatile memory array with resistive sense element block erase and uni-directional write

A magnetic memory cell that includes at least two magnetoresistive memory bits is presented. The memory cell is capable of storing at least two logical states. The first logical state occurs when the bits share the same orientation, such as a parallel orientation or an antiparallel orientation. The second logical state occurs when the bits have opposite orientations. In the second logical state one of the bits has a parallel orientation and the other bit has an antiparallel orientation.

Two-element magnetic memory cell

A magneto-resistive memory system is presented that includes a radiation-hardened and low power memory cell. The magneto-resistive memory cell includes a word line select transistor in the cell to help eliminate unselected cell disturbances. Furthermore, the magneto-resistive memory cell includes a full-turn write word line that writes true and complimentary bit values using less current than previous cell architectures. The improved memory cell may be used in a memory system with precision current drivers and auto-zero sense amplifiers in order to further lower power and improve overall system reliability.

Complementary giant magneto-resistive memory with full-turn word line

In a method of fabricating a giant magnetoresistive (GMR) device a plurality of magnetoresistive device layers is deposited on a first silicon nitride layer formed on a silicon oxide layer. An etch stop is formed on the magnetoresistive device layers, and a second layer of silicon nitride is formed on the etch stop. The magnetoresistive device layers are patterned to define a plurality of magnetic bits having sidewalls. The second silicon nitride layer is patterned to define electrical contact portions on the etch stop in each magnetic bit. The sidewalls of the magnetic bits are covered with a photoresist layer. A reactive ion etch (RIE) process is used to etch into the first silicon nitride and silicon oxide layers to expose electrical contacts. The photoresist layer and silicon nitride layers protect the magnetoresistive layers from exposure to oxygen during the etching into the silicon oxide layer.

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Maple Plain, MN, United States of America

Daniel Seymour Reed