Read Rite Corporation

Western Digital (fremont), Inc.

Nano-write Corporation

Kenneth E Knapp

Ronald A Barr

James Spallas

Benjamin P Law

Zhupei Shi

Matthew R Gibbons

Robert Earl Rottmayer

Lien-Chang Wang

Ming Zhao

Liubo Hong

Kyusik Sin

Mark David Thomas

Yiming Huai

Chih-Huang Lai

Billy Wayne Crue

Billy W Crue, Jr

Zi-Wen Dong

Francis W Ryan

Bill Crue

Myron R Cagan

Russel Stearns

Robert E Rotmayer

Chuck Rose

Jain-Gang Zhu

Michael L Hedrick

A method and system for forming a microscopic transducer are described. The method and system include forming a plurality of adjoining sensor layers. The sensor layers include a first magnetically soft layer, a nonmagnetic layer on the first magnetically soft layer, and a second magnetically soft layer on the nonmagnetic layer. The method and system also include forming a sidewall over the second magnetically soft layer. The sidewall formation includes forming a base having a surface oriented substantially perpendicular to the sensor layers and depositing an electrically conductive material on the surface. The method and system also include removing a portion of the sensor layers not covered by the sidewall.

Method of making narrow track width magnetoresistive sensor

Methods are provided for forming current perpendicular to the plane thin film read heads. In one embodiment, the method comprises the steps of forming a lower sensor lead, forming a lower sensor lead cladding of a low sputter yield material on the lower sensor lead, forming a sensor element on the lower sensor lead cladding, and forming an upper sensor lead coupled to the sensor element. The low sputter yield material helps to reduce redeposition of the lower sensor lead material onto side walls of the sensor element as the sensor element is being formed.

Methods for fabricating redeposition free thin film CPP read sensors

A trailing pole-tip for an electromagnetic transducer is formed as a layer oriented substantially perpendicular to other layers of the transducer, allowing the pole-tip to be made much thinner than conventional pole-tips. The novel pole-tip is formed on an edge or sidewall of a base layer instead of being formed on top of an existing layer. Potential errors in pole-tip thickness are much less than standard error tolerances for conventional pole-tip thickness. Having a greatly reduced pole-tip width significantly reduces the track width so that many more tracks can fit on a media surface, providing a large increase in areal density.

Submicron track-width pole-tips for electromagnetic transducers

A coating for a biomedical device is disclosed, including a metal layer and/or a ceramic layer, such as a layer of titanium (Ti) and a layer of titanium-nitride (TiN). The coating can form a coping for a crown for a tooth, the crown including a porcelain layer bonded to the titanium-nitride (TiN) layer. Methods for making and using a biomedical device are also disclosed, including vapor deposition of metal and/or ceramic layers, such as titanium (Ti) and titanium-nitride (TiN) layers. In one embodiment, the method includes forming a titanium (Ti) vapor that solidifies to form a titanium (Ti) layer; forming a titanium-nitride (TiN) vapor that coats the titanium (Ti) layer with a titanium-nitride (TiN) layer; and forming a porcelain layer on the titanium-nitride (TiN) layer. The porcelain can be sintered to form a dental crown or other device.

Vapor deposited titanium and titanium-nitride layers for dental devices

The present invention provides an improved current perpendicular to the plane thin film read head device and method of fabrication. With the present invention, the lower lead is formed to inhibit accumulation of redeposited lead material on CPP sensor element side walls during CPP sensor formation. In the preferred embodiment, the upper portion of the lower lead, which normally is etched during sensor element formation, is formed of a low sputter yield material to reduce redeposition flux to the sensor side walls. It is also preferred to form the upper portion of a material that also has a low value for the ratio of its sputter yield at the lead milling angle-to-its sputter yield at the side wall milling angle to inhibit redeposition accumulation on the side wall. It is preferred to clad conventional lead material with a low sputter yield ratio, low resistivity material, to inhibit side wall redeposition accumulation while also providing a low resistance lower lead. The underlying lead material may be formed of conventional low resistance lead materials with a cladding of a refractory metal, such as tantalum, titanium, tungsten, molybdenum, zirconium, vanadium, niobium, their alloys, or the like. The improved CPP read head of the present invention may be embodied in a data storage and retrieval apparatus.

Structure and method for redeposition free thin film CPP read sensor fabrication

Methods for reducing feature sizes of devices such as electromagnetic sensors are disclosed. A track width of a MR sensor is defined by a mask having an upper layer with a reduced width and a lower layer with a further reduced width. Instead of or in addition to being supported by the lower layer in the area defining the sensor, the upper layer is supported by the lower layer in areas that do not define the sensor width. In some embodiments the upper layer forms a bridge mask, supported at its ends by the lower layer, and the lower layer is completely removed over an area that will become a sensor. Also disclosed is a mask having more than two layers, with a bottom layer completely removed over the sensor area, and a middle layer undercut relative to a top layer.

Magnetoresistive sensors having submicron track widths and method of making

Data storage and retrieval apparatus with thin film read head having inset extra gap insulation layer and method of fabrication

The present invention provides an improved bias magnet-to-magnetoresistive element interface and method of fabrication. In a preferred embodiment, the wall/walls of an MR element opposing a bias layer are formed by over etching to provide vertical side walls without taper. In the preferred embodiment, a protective element is formed over the MR element to protect it during etch processes. In some embodiments, a filler layer is deposited prior to bias layer formation. In CIP embodiments, any portion of the filler layer forming on vertical side walls of the MR element is etched to provide an exposed side wall surface for contiguous bias layer formation. In CPP embodiments, the filler layer forms on a vertical back wall and electrically insulates the MR element from the bias layer. In CIP and CPP embodiments, tapered portions of the bias material, which form overhanging the MR element, are removed by directional etching to improve the direction and stability of the induced longitudinal field within the MR element. In some CIP embodiments, tapered overhang removal allows for formation of improved lead structures, which may be deposited on the MR element closer to the side walls, and which are not pinched off by the overhang of an underlying bias layer, thus improving current density profile and definition of the actual effective track width of the device.

Thin film read head structure with improved bias magnet-to-magnetoresistive element interface and method of fabrication

An electrically conductive sidewall for an electromagnetic transducer having a magnetoresistive sensor is formed as a layer oriented substantially perpendicular to other layers of the sensor, and is used as a mask for defining the width of the sensor. This allows the sensor to be made much thinner than conventional sensors, providing higher resolution in a track width direction. The sidewall can be nonmagnetic, serving as a spacer between the magnetic sensor layers and an adjacent magnetic shield without the need for a protective cap to guard against damage from polishing and wet etching. Alternatively, the sidewall can be magnetic, serving as an extension of the shield. In either case, the sidewall reduces the effective length of the sensor for linear resolution, sharpening the focus of the sensor and increasing linear density. Also reduced is the tolerance for error in sensor width and length. The combination of increased resolution in track width and track length directions provides a large increase in areal resolution, such that sensors in accordance with the present invention may be able to resolve signals at a density exceeding a terabit per square inch. A correspondingly narrow pole-tip for an inductive transducer that may be employed in conjunction with the magnetoresistive sensor is also disclosed.

Narrow track width magnetoresistive sensor and method of making

A magnetoresistive device includes a metal layer, formed over a substrate, in which a groove is formed. A magnetoresistive element is formed in the groove, forming two magnetoresistive element portions that are separated by a conductive element. A sense current applied to the metal layer flows through the two magnetoresistive element portions with a predominant current-perpendicular-to-plane component. The method includes techniques that are less complex and less expensive than submicron photolithography to form the above described magnetoresistive device with submicron geometries.

CPP magnetoresistive device and method for making same

A magnetoresistive (MR) transducer has at least one insulative layer made of tetrahedral amorphous carbon (ta-C). The ta-C layer is formed by filtered cathodic arc deposition, has an essentially zero concentration of hydrogen and can serve as a read gap for the transducer. The hydrogen-free t-aC read gap has high thermal conductivity, keeping an adjoining MR sensor from overheating during operation. This extends sensor lifetimes and/or improves sensor performance. The read gap also has low defects and porosity, preventing unwanted electrical conduction or shorting between a sensor and a shield. The high hardness of the read gap resists plasma and chemical etching processes such as ion milling that are used to form the sensor. The increased hardness and reduced defects and porosity allow the read gaps to be made thinner without risking electrical shorting. Other hydrogen-free t-aC layers are employed for other sensor elements where electrical insulation and reduced thickness are important.

Insulator layers for magnetoresistive transducers

The present invention provides an exchange break to define the track width of a read head by selectively isolating an exchange coupling layer from an underlying ferromagnetic layer. In the preferred embodiment, the exchange break is provided over a portion of the free layer of a spin valve device so that it inhibits exchange coupling between an overlying portion of the exchange coupling layer and the underlying free layer to define an active region. It is preferred to form the exchange break of an electrically insulating material, to inhibit current shunting through the exchange break, and of a material that easily etches, to minimize inadvertent etching of the underlying free layer and to ensure complete removal of exchange break material when forming the exchange break from an exchange break layer. A reentrant profile photoresist structure may be used to define the exchange break and to define the exchange coupling layer. Drift portions of the exchange coupling layer, which typically form under the overhang of the photoresist and blur delineation of the active region, are separated from the underlying free layer by the exchange break, so that variations in thickness and in shifted material composition do not blur active region delineation. Because the width of the active region is defined by the exchange break, the present invention decouples the track width of the device from the geometry of the exchange coupling layer.

Growing community of inventors

Livermore, CA, United States of America

Kenneth E Knapp