Headway Technologies, Incorporated

Magic Technologies, Inc.

International Business Machines Corporation

Taiwan Semiconductor Manufacturing Comp. Ltd.

Applied Spintronics, Inc.

Sae Magnetics (h.k.) Limited

Applied Spintronics Technology, Inc.

Other

Applied Spintronill, Inc.

Applied Spintadnics, Inc.

Po-Kang Wang

Guenole Jan

Yimin Guo

Huanlong Liu

Yuan-Jen Lee

Ru-Ying Tong

Mao-Min Chen

Jian Zhu

Cherng-Chyi Han

Tai Min

Xizeng Shi

Moris Musa Dovek

Kochan Ju

Chyu-Jiuh Torng

Hsu Kai Yang

Mohamad Towfik Krounbi

Cheng Tzong Horng

Jodi Mari Iwata

Bruce Yee Yang

Kenichi Takano

Luc Thomas

Yoshitaka Sasaki

Yu-Jen Wang

Lijie Guan

Otto Voegeli

Chen-Jung Chien

Hong Tian

Xi Zeng Shi

Ellis T Cha

Dongna Shen

Joe Smyth

Vignesh Sundar

Sahil Patel

Yen Fu

Manuel Hernandez

Yaw-Shing Tang

Kenneth Ting-Yuan Kung

Hsu Kai (Karl) Yang

Ben Hu

Chun Liu

Kunliang Zhang

Erhard Theodor Schreck

Witold Kula

Masanori Sakai

John Kenneth DeBrosse

Neil Leslie Robertson

Ching Hwa Tsang

Hui-Chuan Wang

Yuhui Tang

Jei-Wei Chang

Jonathan Zanhong Sun

Yue Liu

Yaguang Wei

Yun-Fei Li

Kowang Liu

Robert Beach

David Eugene Heim

Yunfei Li

Denny D Tang

Chyu Jiuh Torng

John De Brosse

Lejan Pu

Kouji Shimazawa

Rong-Fu Xiao

Perng-Fei Yuh

Gene Michael Sandler

Robert Fontana

Zhigang Bai

Takehiro Kamigama

Hiroyuki Itoh

Liubo Hong

Yan Wu

Rongfu Xiao

Tom Zhong

Glen A Garfunkel

Jyh-Shuey Jerry Lo

Jiun-Ting Lee

John Stewart Best

Wei Cao

William C Cain

Grace Lim Gorman

David Tsang

James Hsi-Tang Lee

David Hu

Xiaomin Liu

Dong-Hong Li

Son Le

Feiyue Li

Jei Wei Chang

Jen-Wei C Koo

Yin Rong

Jeu-Wei C Koo

Moris Musa Dover

Jyh-Shiliey Jerry Lo

Hao Qing Pan

Cheng-Teh Wu

Tommy Chan

A magnetic tunnel junction is disclosed wherein the reference layer and free layer each comprise one layer having a boron content from 25 to 50 atomic %, and an adjoining second layer with a boron content from 1 to 20 atomic %. One of the first and second layers in each of the free layer and reference layer contacts the tunnel barrier. Each boron containing layer has a thickness of 1 to 10 Angstroms and may include one or more B layers and one or more Co, Fe, CoFe, or CoFeB layers. As a result, migration of non-magnetic metals along crystalline boundaries to the tunnel barrier is prevented, and the MTJ has a low defect count of around 10 ppm while maintaining an acceptable TMR ratio following annealing to temperatures of about 400° C. The boron containing layers are selected from CoB, FeB, CoFeB and alloys thereof including CoFeNiB.

Magnetic tunnel junction with low defect rate after high temperature anneal for magnetic device applications

A magnetic tunnel junction (MTJ) is disclosed wherein a free layer (FL) interfaces with a first metal oxide (Mox) layer and second metal oxide (tunnel barrier) to produce perpendicular magnetic anisotropy (PMA) in the FL. In some embodiments, conductive metal channels made of a noble metal are formed in the Mox that is MgO to reduce parasitic resistance. In a second embodiment, a discontinuous MgO layer with a plurality of islands is formed as the Mox layer and a non-magnetic hard mask layer is deposited to fill spaces between adjacent islands and form shorting pathways through the Mox. In another embodiment, end portions between the sides of a center Mox portion and the MTJ sidewall are reduced to form shorting pathways by depositing a reducing metal layer on Mox sidewalls, or performing a reduction process with forming gas, H, or a reducing species.

Low resistance MgO capping layer for perpendicularly magnetized magnetic tunnel junctions

A method includes receiving tester configuration data, test pattern data, and tester operation data; configuring a circuit for performing a designated test evaluation; generating a stimulus waveform; converting the stimulus waveform to an analog stimulus signal; transferring the analog stimulus signal to a first terminal of a MTJ DUT at reception of a trigger timing signal; generating time traces based on the trigger timing signal; generating a response signal at a second terminal of the MTJ DUT and across a termination resistor as the analog stimulus signal is transferred through the MTJ DUT; converting the response signal to a digitized response signal indicating its voltage amplitude; and performing the designated test evaluation and analysis function in the configurable circuit based on voltage amplitudes and time values of the stimulus waveform, the digitized response signal, and the timing traces.

Electrical testing apparatus for spintronics devices

A magnetic tunnel junction with perpendicular magnetic anisotropy (PMA MTJ) is disclosed wherein a free layer interfaces with a tunnel barrier and has a second interface with an oxide layer. A lattice-matching layer adjoins an opposite side of the oxide layer with respect to the free layer and is comprised of CoFeNiLMor an oxide or nitride of Ru, Ta, Ti, or Si, wherein L is one of B, Zr, Nb, Hf, Mo, Cu, Cr, Mg, Ta, Ti, Au, Ag, or P, and M is one of Mo, Mg, Ta, Cr, W, or V, (x+y+z+w+v)=100 atomic %, x+y&#x3e;0, and each of v and w are &#x3e;0. The lattice-matching layer grows a BCC structure during annealing thereby promoting BCC structure growth in the oxide layer that results in enhanced free layer PMA and improved thermal stability.

Maintaining coercive field after high temperature anneal for magnetic device applications with perpendicular magnetic anistropy

A laminated seed layer stack with a smooth top surface having a peak to peak roughness of 0.5 nm is formed by sequentially sputter depositing a first seed layer, a first amorphous layer, a second seed layer, and a second amorphous layer where each seed layer may be Mg and has a resputtering rate 2 to 30X that of the amorphous layers that are TaN, SiN, or a CoFeM alloy. A template layer that is NiCr or NiFeCr is formed on the second amorphous layer. As a result, perpendicular magnetic anisotropy in an overlying magnetic layer that is a reference layer, free layer, or dipole layer is substantially maintained during high temperature processing up to 400&#xb0; C. and is advantageous for magnetic tunnel junctions in embedded MRAMs, spintronic devices, or in read head sensors. The laminated seed layer stack may include a bottommost Ta or TaN buffer layer.

Fully compensated synthetic ferromagnet for spintronics applications

A magnetic tunnel junction is disclosed wherein the reference layer and free layer each comprise one layer having a boron content from 25 to 50 atomic %, and an adjoining second layer with a boron content from 1 to 20 atomic %. One of the first and second layers in each of the free layer and reference layer contacts the tunnel barrier. Each boron containing layer has a thickness of 1 to 10 Angstroms and may include one or more B layers and one or more Co, Fe, CoFe, or CoFeB layers. As a result, migration of non-magnetic metals along crystalline boundaries to the tunnel barrier is prevented, and the MTJ has a low defect count of around 10 ppm while maintaining an acceptable TMR ratio following annealing to temperatures of about 400&#xb0; C. The boron containing layers are selected from CoB, FeB, CoFeB and alloys thereof including CoFeNiB.

Circuits and methods for programming a MTJ stack of an MRAM cell minimizes a ferromagnetic free layer or pinned layer polarization reversal due to back-hopping. The programming begins by applying a first segment of the segment of the write pulse at a first write voltage level for a first time period to program the MTJ stack. A second segment of the segment of the write pulse at a second write voltage level that is less than the first write voltage level is applied to the magnetic tunnel junction stack for a second time period to correct the polarization of the MTJ when the MTJ stack has reversed polarization during the first time period. The second segment of the segment of the write pulse may be a ramp, or multiple ramps, or have a quiescent period between it and the first segment of the write pulse.

Method and circuits for programming STT-MRAM cells for reducing back-hopping

Methods and circuits for programming STT-MRAM cells for reducing back-hopping

Maintaining coercive field after high temperature anneal for magnetic device applications with perpendicular magnetic anisotropy

A stimulus/response controller within a magnetic electrical test apparatus is configured for generating and transmitting stimulus waveforms to a high-speed DAC for application to a MTJ DUT. The response signal from the MTJ DUT is applied to an ADC that digitizes and transfers the response signal to the stimulus/response controller. The stimulus/response controller has a configurable function circuit that is selectively configured for performing evaluation and analysis of the digitized stimulus and response signals. The configurable functions are structured for performing any evaluation and analysis function for determining the characteristics of the MTJ DUT(s). Examples of the evaluation and analysis operations include averaging the stimulus and/or response signals, determining the differential resistance, the degradation times, failure counts, or the bit error rate of the MTJ DUT(s). The evaluations and analysis of the MTJ DUT are then available for transfer to a tester controller within the magnetic electrical test apparatus.

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San Jose, CA, United States of America

Po-Kang Wang