Headway Technologies, Incorporated

Taiwan Semiconductor Manufacturing Comp. Ltd.

Hgst Netherlands, B.v.

Keyu Pi

Ru-Ying Tong

Yu-Jen Wang

Jian Zhu

Bruce Alvin Gurney

Patrick Braganca

Huanlong Liu

Rehan Ahmed Zakai

Samir Y Garzon

A method of forming a MTJ with a tunnel barrier having a high tunneling magnetoresistance ratio, and low resistance x area value is disclosed. The method preserves perpendicular magnetic anisotropy in bottom and top magnetic layers that adjoin bottom and top surfaces of the tunnel barrier. A key feature is a passive oxidation step of a first Mg layer that is deposited on the bottom magnetic layer wherein a maximum oxygen pressure is 10-5 torr. A bottom portion of the first Mg layer remains unoxidized thereby protecting the bottom magnetic layer from substantial oxidation during subsequent oxidation and anneal processes that are employed to complete the fabrication of the tunnel barrier and MTJ. An uppermost Mg layer may be formed as the top layer in the tunnel barrier stack before a top magnetic layer is deposited.

Method for forming a perpendicular spin torque oscillator (PSTO) including forming a magneto resistive sensor (MR) over a spin torque oscillator (STO)

A method for etching a magnetic tunneling junction (MTJ) structure is described. A stack of MTJ layers is provided on a bottom electrode in a substrate. The MTJ stack is etched to form a MTJ structure wherein portions of sidewalls of the MTJ structure are damaged by the etching. Thereafter, the substrate is removed from an etching chamber wherein sidewalls of the MTJ structure are oxidized. A physical cleaning of the MTJ structure removes damaged portions and oxidized portions of the MTJ sidewalls. Thereafter, without breaking vacuum, an encapsulation layer is deposited on the MTJ structure and bottom electrode.

Physical cleaning with in-situ dielectric encapsulation layer for spintronic device application

A method of forming a hybrid oxide capping layer (HOCL) is disclosed and used in a magnetic tunnel junction to enhance thermal stability and perpendicular magnetic anisotropy in an adjoining free layer. The HOCL has a lower interface oxide layer and one or more transition metal oxide layers wherein each of the metal layers selected to form a transition metal oxide has an absolute value of free energy of oxide formation less than that of the metal used to make the interface oxide layer. One or more of the HOCL layers is under oxidized. Oxygen from one or more transition metal oxide layers preferably migrates into the interface oxide layer during annealing to further oxidize the interface oxide. As a result, a less strenuous oxidation step is required to initially oxidize the lower HOCL layer and minimizes oxidative damage to the free layer.

Hybridized oxide capping layer for perpendicular magnetic anisotropy

A hybrid oxide capping layer (HOCL) is disclosed and used in a magnetic tunnel junction to enhance thermal stability and perpendicular magnetic anisotropy in an adjoining reference layer. The HOCL has an interface oxide layer adjoining the reference layer and one or more transition metal oxide layers wherein each of the metal layers selected to form a transition metal oxide has an absolute value of free energy of oxide formation less than that of the metal used to make the interface oxide layer. One or more of the HOCL layers is under oxidized. Oxygen from one or more transition metal oxide layers preferably migrates into the interface oxide layer during an anneal to further oxidize the interface oxide. As a result, a less strenuous oxidation step is required to initially oxidize the lower HOCL layer and minimizes oxidative damage to the reference layer.

A hybrid oxide capping layer (HOCL) is disclosed and used in a magnetic tunnel junction to enhance thermal stability and perpendicular magnetic anisotropy in an adjoining free layer. The HOCL has a lower interface oxide layer and one or more transition metal oxide layers wherein each of the metal layers selected to form a transition metal oxide has an absolute value of free energy of oxide formation less than that of the metal used to make the interface oxide layer. One or more of the HOCL layers is under oxidized. Oxygen from one or more transition metal oxide layers preferably migrates into the interface oxide layer during an anneal to further oxidize the interface oxide. As a result, a less strenuous oxidation step is required to initially oxidize the lower HOCL layer and minimizes oxidative damage to the free layer.

The embodiments disclosed generally relate to a read device in a magnetic recording head. The read device uses parametric excitation to injection lock the STO to an external AC signal with a frequency that is two times the resonance frequency, or more. The field from the media acting on the STO causes a change in the phase between the STO output and the external locking signal, which can be monitored using a phase detection circuit. The injection locking improves the STO signal to noise ratio and simplifies the detection circuit.

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San Jose, CA, United States of America

Keyu Pi