Seagate Technology Incorporated

Seagate Technologies, Inc.

Andreas Karl Roelofs

Martin Gerard Forrester

Haiwen Xi

Dimitar Velikov Dimitrov

Tong Zhao

Xiaobin Wang

Hongyue Liu

Markus Siegert

Wei Tian

Insik Jin

Olle Gunnar Heinonen

Paul E Anderson

Venugopalan Vaithyanathan

Mark David Bedillion

Earl Chrzaszcz Johns

Yongchul Ahn

Muralikrishnan Balakrishnan

Markus Jan Peter Siegert

Eileen Yan

Edward Stephen Skalko

Xueshi Yang

Song Sheng Xue

Wenzhong Zhu

Yiran Chen

Hai Li

Harry Hongyue Liu

Joachim Walter Ahner

Robert Earl Rottmayer

Florin Zavaliche

Alan Xuguang Wang

Mark Ian Lutwyche

Cedric Bedoya

Dierk Guenter Bolten

Yongjun Zhao

Andre Y L Liem

Method and apparatus for writing data to a magnetic memory cell, such as a spin-torque transfer random access memory (STRAM) memory cell. In accordance with various embodiments, a write current is applied through a selected magnetic memory cell to initiate magnetic precession of the selected cell to a desired magnetic state. A field assist current is concurrently flowed through an adjacent memory cell to generate a magnetic field that assists in the precession of the selected cell to the desired magnetic state.

Using a nearby cell to provide field assisted switching in a magnetic memory array

A resistive sense memory cell includes a layer of crystalline praseodymium calcium manganese oxide and a layer of amorphous praseodymium calcium manganese oxide disposed on the layer of crystalline praseodymium calcium manganese oxide forming a resistive sense memory stack. A first and second electrode are separated by the resistive sense memory stack. The resistive sense memory cell can further include an oxygen diffusion barrier layer separating the layer of crystalline praseodymium calcium manganese oxide from the layer of amorphous praseodymium calcium manganese oxide a layer. Methods include depositing an amorphous praseodymium calcium manganese oxide disposed on the layer of crystalline praseodymium calcium manganese oxide forming a resistive sense memory stack.

Non-volatile resistive sense memory with improved switching

A method and apparatus for testing an array of non-volatile memory cells, such as a spin-torque transfer random access memory (STRAM). In some embodiments, an array of memory cells having a plurality of unit cells with a resistive sense element and a switching device has a row decoder and a column decoder connected to the plurality of unit cells. A test circuitry sends a non-operational test pattern through the array via the row and column decoders with a quiescent supply current to identify defects in the array of memory cells.

Quiescent testing of non-volatile memory array

Memory units that have a magnetic tunnel junction cell that utilizes spin torque and a current induced magnetic field to assist in the switching of the magnetization orientation of the free layer of the magnetic tunnel junction cell. The memory unit includes a spin torque current source for passing a current through the magnetic tunnel junction cell, the spin torque current source having a direction perpendicular to the magnetization orientations, and also includes a magnetic ampere field current source is oriented in a direction orthogonal or at some angles to the magnetization orientations.

Magnetic field assisted stram cells

Non-volatile resistive sense memory with praseodymium calcium manganese oxide

Magnetic field assisted STRAM cells

Magnetic shift registers in which data writing and reading is accomplished by moving the magnetic domain walls by electric current. Various embodiments of domain wall nodes or anchors that stabilize a domain wall are provided. In some embodiments, the wall anchors are elements separate from the magnetic track. In other embodiments, the wall anchors are disturbances in the physical configuration of the magnetic track. In still other embodiments, the wall anchors are disturbances in the material of the magnetic track.

Magnetic tracks with domain wall storage anchors

The presently disclosed technology teaches an improved voltage pattern for conductive tips utilized as moveable top electrodes for writing data bits into ferroelectric media. A conductive tip is dragged in contact or near contact with a ferroelectric surface forming a moveable top electrode on a ferroelectric media disk. A metallic film is deposited onto a bottom-side of the ferroelectric media forming a conductive bottom electrode. Applying electrical voltage pulses between the conductive tip and the bottom electrode induces polarization switching of the ferroelectric media under the head. The improved voltage pattern incorporates positive and negative overshoot voltages to induce a polarization switch in the ferroelectric media and positive and negative drag voltages to expand a polarized region on the ferroelectric media. Potential benefits of the improved voltage pattern include reduced cross-track blooming and reduced along-track blooming resulting in a more uniform track width and bit series length.

Voltage pattern for ferroelectric recording head

An apparatus includes a storage medium, and a transducer positioned adjacent to the storage medium, wherein the transducer includes a first electrode and a second electrode, with the width of the first electrode being less than the width of the second electrode. A method including: applying a first voltage to a transducer to write data to a storage medium, and applying a second voltage to the transducer to read data from the storage medium, wherein the magnitude of the first voltage is greater than the magnitude of the second voltage.

Probe head with narrow read element

A register having a track with a first electrode is at the first end to supply a current to the track in a first direction and a second electrode at the second end to supply a current to the track in a second direction, the second direction being opposite to the first direction. A first domain wall anchor and a second domain wall anchor are positioned proximate the track between the first electrode and the second electrode. Each of the domain wall anchors has a ferromagnetic pinned layer and a barrier layer proximate the track, with the barrier layer between the track and the ferromagnetic pinned layer. The ferromagnetic layer has a magnetization orientation pinned perpendicular to the magnetization orientation of the track.

Magnetic shift register as counter and data storage device

An apparatus that provides for non-destructive readback of a ferroelectric material. The apparatus can include a ferroelectric layer with a scannable surface wherein the ferroelectric layer has a compensation charge adjacent the scannable surface. The apparatus also can include an electrode adjacent the scannable surface to sense the compensation charge. A related method is also disclosed.

Non-destructive readback for ferroelectric material

An apparatus includes a first ferroelectric storage layer and a second ferroelectric storage layer adjacent the first ferroelectric storage layer. A coupling layer may be between the first ferroelectric storage layer and the second ferroelectric storage layer. The ferroelectric storage layers may be configured as a data storage medium for use in a data storage system. A related method is also disclosed.

Multiple ferroelectric films

A single annealing process simultaneously creates local areas of ferroelectric imprint that can be used as markers, and areas with low leakage current that exhibit ideal symmetric switching on ferroelectric recording media.

Ferroelectric media with robust servo marks and storage areas with low leakage current

An apparatus comprises mechanically scanned ferroelectric data storage media. A scanning electrode contacts the scannable surface with a contact force. The ferroelectric data storage media generates a piezoelectric potential that is picked up by the electrode. The piezoelectric potential has a polarity that varies as a function of data polarity on the data storage media.

Piezoelectric reading of ferroelectric data storage media

A method of writing to ferroelectric storage medium includes the steps of applying a first write voltage to a ferroelectric layer for writing a first bit in a first polarization direction and applying a second write voltage to the ferroelectric layer for writing a second bit in a second polarization direction opposing the first polarization direction. The first write voltage having a first magnitude, and the second write voltage having a second magnitude being greater than the first magnitude. The ferroelectric layer having a ferroelectric imprint polarization direction, and the first polarization direction being substantially the same as the ferroelectric imprint polarization direction. The ferroelectric medium contains first bits with a first surface area that is substantially equal to second bits surface area. A probe storage apparatus can use this method and ferroelectric medium.

Asymmetric write for ferroelectric storage

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Eden Prairie, MN, United States of America

Andreas Karl Roelofs