Seagate Technology Incorporated

Western Digital Technologies, Inc.

Sandisk Technologies Inc.

Hans Jurgen Richter

Erol Girt

Mariana Rodica Munteanu

Thomas P Nolan

Michael Grobis

David S Kuo

Kim Yang Lee

Ward M Parkinson

Dieter Klaus Weller

James E O'Toole

Nathan Franklin

Thomas Michael Trent

Michael Nicolas Albert Tran

James W Reiner

Richard Michael Brockie

Felix Trejo

Jianping Chen

Technology for read in a cross-point memory array. Drive transistors pass read and write currents to the cross-point memory array. The read current charges a selected word line to turn on a threshold switching selector of a selected memory cell. While the threshold switching selector is on, the current (read or write) passes through the selected memory cell. The memory system applies a smaller overdrive voltage to a drive transistor when the drive transistor is passing the read current than when the drive transistor is passing the write current. A smaller overdrive voltage increases the resistance of the drive transistor. Increasing the resistance of the drive transistor increases the resistance seen by the threshold switching selector in the selected memory cell, which reduces the Ihold of the threshold switching selector.

Cross-point array IHOLD read margin improvement

Technology is disclosed for a memory system having a cross-point array with threshold switching selector memory cells. Each memory cell has a two-terminal threshold switching selector memory element that may be programmed to two different on-state conductances in order to store information. One bit value may be represented by a high-resistance state (HRS) when in the on-state and another bit value may be represented by a low-resistance state (LRS) when in the on-state. In one aspect, a conditioning signal is applied to the memory cell prior to programming. Applying a program signal with the opposite polarity as the conditioning signal may result in a higher conductance in the on-state than applying a program signal with the same polarity as the conditioning signal. The memory element may also serve as a selector for the memory cell. The memory element may include an Ovonic Threshold Switch (OTS).

Cross-point array with threshold switching selector memory element

A ferromagnetically coupled magnetic recording medium having a first ferromagnetic layer, a second ferromagnetic layer, and a ferromagnetic coupling layer to ferromagnetically couple the first ferromagnetic layer to the second ferromagnetic layer is used as stable magnetic media with high MT in high density recording hard drives. The first ferromagnetic layer is the stabilization layer and the second ferromagnetic layer is the main recording layer. The ferromagnetic coupling layer comprises a conductive material having a thickness which produces ferromagnetic coupling between said first ferromagnetic layer and said second ferromagnetic layer via the RKKY interaction.

Feromagnetically coupled magnetic recording media

A low-coupling perpendicular magnetic recording media comprising a magnetic storage layer and at least one low saturation magnetization layer. The magnetic storage layer has a saturation magnetization between about 400-900 emu/cm3 and the at least one low saturation magnetization layer has a saturation magnetization below that of the magnetic storage layer.

Low-coupling oxide media (LCOM)

A method of making a disc for a computer disc drive and a disc made in accordance with the same. The disc includes a deposited magnetic layer of a thin film medium over a disc-shaped substrate. A master pattern having a plurality of tracks is recorded on the disc. Each track on the disc includes a plurality of magnetic islands, each having a size and magnetic properties. The size and/or magnetic properties of one or more of the magnetic islands of each track are modulated such that each track has a modulation frequency, so as to imprint a magnetic topology on the disc. The modulation frequency of each track is either a fundamental frequency or an overtone of the fundamental frequency.

Embedded servo on track for bit-patterned device

A low-coupling perpendicular magnetic recording media comprising a magnetic storage layer and at least one low saturation magnetization layer. The magnetic storage layer has a saturation magnetization between about 400-900 emu/cmand the at least one low saturation magnetization layer has a saturation magnetization below that of the magnetic storage layer.

Low coupling oxide media (LCOM)

Method for energy barrier equalization of magnetic recording media and media obtained thereby

A method for measuring the width of an erase band located adjacent to a test track containing a periodic signal at a specified frequency is disclosed. For each position of a read head as it incrementally traverses the erase band and test track, an information signal is read, and a signal level data point is stored which represents the amplitude of the fundamental frequency obtained from a Fourier transform of the information signal. In addition, a media noise level data point is stored which represents an integration of a noise power spectrum obtained from the Fourier spectrum of the information signal over a predetermined frequency range. Once the signal and media noise level data points are obtained, the edge of the test track is approximated by determining from the signal level data points a point at which the amplitude of the stored signal level data points departs from an otherwise substantially constant background noise level. The edge of the erase band is also approximated by determining from the media noise level data points a point at which the amplitude of the stored media noise level data points departs from an otherwise substantially constant background noise level. The width of the erase band is derived by computing the absolute value of the difference between the positions of the edge of the test track and the edge of the erase band.

System and method for measuring erase band widths on magnetic media

Growing community of inventors

Palo Alto, CA, United States of America

Hans Jurgen Richter