International Business Machines Corporation

Hitachi Global Storage Technologies Netherlands B.v.

Apple Inc.

Kovio, Inc.

Alfred Floyd Renaldo

Douglas Johnson Werner

Dennis R McKean

Gregory Breyta

Mustafa Pinarbasi

Robert Dennis Miller

Mohamad Towfik Krounbi

Willi Volksen

Howard Gordon Zolla

John David Westwood

Robert John Wilson

Saad K Doss

Jane Ellyn Nealis

Mahbub R Khan

Murali Ramasubramanian

Ion Bita

Joerg Rockenberger

Christopher S Gudeman

Randall George Simmons

Mark Whitney Hart

Ian Robson McFadyen

Daniel Joseph Dawson

Daniel Wayne Bedell

Criswell Choi

An-Chun Tien

Clayton Ka Tsun Chan

Brian N Hubert

Bulent Nihat Kurdi

Sudirukkuge T Jinasundera

Thomas Carl Clarke

Ronald P Esch

Benjamin L Wang

April Dawn Hixson-Goldsmith

Tom King Harris, Iii

Ranjith Samuel E John

Jie Fu

Laser lift-off methods are described in which optical flatness is provided on the back side of a temporary substrate using either an optical layer or optical liquid. A laser is directed through the optical layer or optical liquid and a back side of the temporary substrate to decompose a portion of a process layer supported on a front side of the temporary substrate, followed by separation of the process layer and the temporary substrate.

Surface modification process for laser application

A read sensor for a magneto resistive head is formed through the use of a bilayer lift-off mask. According to one embodiment, a release layer is formed on top of a sensor layer. A silicon-containing resist layer is formed over the release layer. The resist layer is patterned according to the desired dimensions of the read sensor. Then, plasma etching, such as oxygen plasma etching, is used to remove the portion of the release layer that is exposed by removal of resist material. The release layer may be etched to undercut the patterned resist layer, or may entirely removed beneath the patterned resist layer to provide a bridge of the resist material. In either case, isotropic plasma etching, anisotropic plasma etching, or some combination thereof may be applied.

Method for manufacturing a read sensor for a magnetoresistive head

Method of plating using a polymeric barrier layer including a polyphenolic polymer which has a repeating unit of the formula: wherein R, R, R, R, and Rare individually hydrogen, a hydroxy group or an azo dye.

Plating using copolymer

Materials, compounds and compositions for radiation patternable functional thin films, methods of synthesizing such materials and compounds, and methods for forming an electronically functional thin film and structures including such a film. The compounds and compositions generally include (a) nanoparticles of an electronically functional material or substance and (b) ligands containing a (photo)reactive group. The method generally includes the steps of (1) irradiating the compound and/or composition, and (2) curing the irradiated compound and/or composition, generally to form an electronically functional film. The functional thin film includes a sintered mixture of nanoparticles. The thin film exhibits improved morphology and/or resolution relative to an otherwise identical structure made by an identical process, but without the (photo)functional group on the ligand, and/or relative to an otherwise identical material patterned by a conventional graphics art-based printing process. The present process also exhibits improved throughput relative to conventional photolithographic processing, by eliminating a metal deposition step. The present invention advantageously provides functional thin film structures having qualities suitable for use in electronics applications, such as display devices or RF ID tags, while enabling elimination of a number of conventional photolithographic processing steps (e.g., functional material sputtering, PECVD, etc.).

Radiation patternable functional materials, methods of their use, and structures formed therefrom

A process for planarizing a patterned metal structure for a magnetic thin film head includes the steps of applying an encapsulation/planarizing material on a substrate, spinning the substrate in a photoresist spinner or similar machine, curing the encapsulation/planarizing layer by energetic particles such as an electron beam. The planarizing process further comprises the step of polishing the entire structure using a conventional chemical-mechanical polishing step. The curing step takes place at the substrate temperature less than 200&#xb0; C., which prevents the damages of the thin film head structures such as MR and GMR sensors. This process is cheap, efficient and easy to apply.

Process for planarizing patterned metal structures for magnetic thin film heads

A material is deposited on a substrate by depositing a liftoff layer overlying the substrate, thereafter depositing a hard-mask layer overlying the liftoff layer, thereafter depositing an image layer in registry with a retained portion of the hard-mask layer, leaving a nonretained portion of the hard-mask layer which is not in registry with the image layer. The method further includes removing the nonretained portion of the hard-mask layer, removing at least a part of the thickness of the image layer, and removing a nonretained portion of the liftoff layer, which may include an undercut under the hard-mask layer. The deposited material is deposited onto the substrate from a source, and the retained portion of the hard-mask layer and any part of the liftoff layer remaining between the hard-mask layer and the substrate is thereafter removed.

Fabrication process using a thin liftoff stencil formed by an image transfer process

A method of forming a read sensor that has a very narrow track width is disclosed. The method involves forming a thin lift-off mask over a central region of a sensor layer, which is subsequently ion-milled and deposited with hard bias and lead layers. The thin lift-off mask is made by forming a release layer over the sensor layer; forming a hardmask layer over the release layer; forming a photoresist layer over the hardmask layer; imaging and developing the photoresist layer such that end portions of the photoresist layer are removed and a central portion of the photoresist layer remains; reactive ion etching (RIE) the hardmask layer such that end portions of the hardmask layer are removed and a central portion of the hardmask layer remains; stripping the central portion of the photoresist layer; and etching the release layer such that end portions of the release layer are removed and a central portion of the release layer remains. The hardmask layer may be made from a highly-etch-resistant material, such as silicon, titanium, or tantalum. The release layer may be made from, e.g., polydimethylglutarimide (PMGI) which may be RIE'd, or a metal (such as AlCu) which may be wet-etched. Using this method, shadowing can be minimized and undercut size can be sufficiently controlled for defining narrow track widths.

Method of forming a read sensor using a lift-off mask having a hardmask layer and a release layer

A projection structure is deposited on a substrate having a top surface by applying a negative photoresist overlying the substrate, and positioning a mask overlying the substrate and lying in a mask plane generally parallel to the top surface. The mask is a negative mask that is opaque in a region defining a location where the projection structure is to be deposited. The method further includes exposing the negative photoresist through the mask, baking and developing the exposed negative photoresist, and depositing the projection structure through the exposed and etched negative photoresist.

Deposition of a projection structure on a substrate using a negative mask and negative photoresist

The magnetic tape recording head of the present invention is formed with magnetic poles that are comprised of a laminated NiFeN/FeN structure. The method for fabricating the magnetic poles utilizes an additive photolithographic technique including a bilayer liftoff resist. In this fabrication method magnetic pole trenches are formed in the bilayer liftoff resist such that an undercut exists in the liftoff layer. Thereafter, the laminated NiFeN/FeN structure is sputter deposited into the trench, followed by the wet chemical removal of the bilayer resist.

Bilayer liftoff process for high moment laminate

A process for planarizing a patterned metal structure for a magnetic thin film head includes the steps of applying an encapsulation/planarizing material on a substrate, spinning the substrate in a photoresist spinner or similar machine, curing the encapsulation/planarizing layer by energetic particles such as an electron beam. The planarizing process further comprises the step of polishing the entire structure using a conventional chemical-mechanical polishing step. The curing step takes place at the substrate temperature less than 200&deg; C., which prevents the damages of the thin film head structures such as MR and GMR sensors. This process is cheap, efficient and easy to apply.

An antireflective composition includes a polyphenolic polymer which has a first repeating unit and a second repeating unit of the formula:

Antireflective polymer and method of use

A method makes a highly defined bilayer lift-off mask wherein lift-off mask material is subjected to an electron beam for decreasing the molecular weight of a bottom release layer and increasing the molecular weight of a top photoresist layer so that a weak developer can be employed for patterning the bottom release layer and ion milling, which is employed for removing layers not covered by the lift-off mask, does not alter a track width of the top photoresist layer.

Method of making highly defined bilayer lift-off mask

An improved process for making thin film magnetic heads using an insulation comprising a polymer, a crosslinking agent, and 4-sulfonate diazonaphthoquinone.

Process for making a thin film magnetic head

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San Jose, CA, United States of America

Alfred Floyd Renaldo