Komag Corporation

Xerox Corporation

Other

Asahi Glass Company, Limited

Tu Chen

Tsutomu Tom Yamashita

Rajiv Yadav Ranjan

Gerardo Bertero

Ronald Allen

Ting Joseph Yuen

Keith Kadokura

John Ko-Jen Chen

Ching-Cheng Shir

Miaogen Lu

Makoto Imakawa

Michinobu Suekane

Charles Changqing Chen

David Treves

Pietro Luigi Cavallotti

Kyou H Lee

Ga-Lane Chen

Thomas Anthony O'Dell

Caroline Anne Ross

Wen Hong Liu

Mark D Moravec

Phuong Binh Nguyen

Wei Cao

Toru Iseda

Kazuo Mannami

Javier Wong

Kazuhiko Mitarai

George B Charlan

John Ko-Chen Chen

Gang Peng

Tam Huu-Minh Nguyen

Tracy L Scott

Yasuo Sakane

John K-j Chen

A Co-Pt based magnetic alloy which has been doped with a relatively high amount of nitrogen, e.g., or above 1 at. % is obtained having high coercivity, for example in the range of 1400 Oe or above, and an increased signal-to-noise ratio as compared to the same Co-Pt based alloy which has not been doped with nitrogen. The alloy is vacuum deposited, for example, by sputtering, and the nitrogen may be introduced from the sputtering gas or from the sputtering target. Other low-solubility elements providing the grain uniformity and isolation include: B, P, S, C, Si, As, Se and Te.

Thin film magnetic alloy having low noise, high coercivity and high squareness

A magnetic medium having at least two intermediate layers between an underlayer and a magnetic layer. The first intermediate layer is designed to provide a good lattice match to the underlayer, while the second intermediate layer is designed to provide a good lattice match to the magnetic layer. Typically, the underlayer has one structure, such as body centered cube, while the magnetic layer has a second structure such as hexagonal close pack. In preferred embodiments, the transition from the one structure to the other structure occurs in the intermediate layers. For example, the first intermediate layer may be a hexagonal close pack structure. Because of the mismatch between the underlayer and the first layer, there may be crystal defects in this first intermediate layer. However, any remaining stress and mismatch is absorbed through the second layer, so that the second layer presents a substantially defect-free surface on which the magnetic layer may grow. Because the second layer is closely matched to the magnetic layer, the magnetic layer continues to grow in a defect-free fashion. In other embodiments of the present invention, a spacer layer having a hexagonal close pack structure may be used between two or more portions of a magnetic layer.

Magnetic thin film recording media having extremely low noise and high thermal stability

In this invention, an ultra thin layer of CoCr alloy nucleation layer is sputtered at an extremely low deposition rate above a predominantly (200) oriented Cr film followed by a CoCrPt based alloy sputtered film at higher rates and moderate temperatures. This structure creates a media which has very high Hc, and excellent PW50, low noise and excellent low TNLD values. By using this technique, the CoCrPt magnetic film achieves excellent in-plane crystallographic orientation, and high Hc is achieved with minimal amount of Pt addition to the magnetic film. The method allows very fine grain structure of cobalt to be formed which contributes to good signal to noise ratio. A fine grain structure combined with chromium segregation between the grains improve the signal to noise ratio even more. A high degree of in-plane c-axis orientation is achieved in the cobalt layer which provides very high hysteresis loop squareness which helps to improve the OW and TNLD. The perfection of the grains is very high so that high anisotropy is obtained in the magnetic layer, resulting in high Hc without the necessity of addition of high level of Pt. The high degree of crystalline perfection also contributes to low TNLD.

Ultra-thin nucleation layer for magnetic thin film media and the method for manufacturing the same

A method for improving corrosion resistance while maximizing magnetic performance of a magnetic disk employed in data storage applications. The invention includes providing a substrate and forming a first layer above the substrate, the first layer having a first degree of abrasion resistance. The invention includes forming a second layer such as a Ni-containing layer above the first layer, the Ni-containing layer having a second degree of abrasion resistance lower than the first degree of abrasion resistance. The invention further includes forming grooves in the Ni-containing layer.

Multi-layer texture layer

A method of manufacturing a magnetic disk includes the steps of depositing a sublayer, a Cr layer and a Co based magnetic layer on a substrate. The sublayer causes the Cr crystals to avoid growing with a predominantly (200) orientation. Because of this the magnetic layer will be isotropic in the film plane and independent of any texture or scratch marks in the substrate.

Method of making high performance, low noise isotropic magnetic media

Ultra-thin nucleation layer for magnetic thin film media and the method

Sputtering method for producing amorphous hydrogenated carbon thin films with high sp.sup.3 content. By sputtering the carbon with a pulsed DC power supply having high voltage peaks, a carbon film with remarkably high sp.sup.3 bonding fraction can be obtained. Previously, carbon films with a very high sp.sup.3 fraction film with content as high (e.g. as 80%) could only be produced by methods such as filtered cathodic arc deposition or chemical vapor deposition methods (CVD) such as plasma-enhanced chemical vapor deposition (PE-CVD) and ion-beam deposition operating at some narrowly defined range of deposition conditions. It is very advantageous to use sputtering to create a high sp.sup.3 content film, since sputtering is more manufacturable and has higher productivity compared to CVD or ion-beam deposition methods. The resultant carbon film has excellent durability and corrosion resistance capability down to very low thickness. Also compared to PE-CVD and ion-beam deposition, the new sputtering process produce much less particles and the process can be run on a manufacturing tool for much longer time, thereby increasing the productivity of the machine, and providing disks with higher quality.

Method of sputtering a carbon protective film on a magnetic disk with

A method for texturing a glass ceramic substrate comprising the steps of applying a laser pulse to the substrate such that a portion of said substrate is heated to a temperature higher than the glass transition temperature of the glass phase of said substrate but lower than the melting point of the crystal phase of said substrate.

Method for laser texturing a glass ceramic substrate and the resulting

A Co--Pt based magnetic alloy which has been doped with a relatively high amount of nitrogen, e.g., at or above 1 at. % is obtained having high coercivity, for example in the range of 1400 Oe or above, and an increased signal-to-noise ratio as compared to the same Co--Pt based alloy which has not been doped with nitrogen. The alloy is vacuum deposited, for example, by sputtering, and the nitrogen may be introduced from the sputtering gas or from the sputtering target. Other low-solubility elements providing the grain uniformity and isolation include: B, P, S, C, Si, As, Se and Te.

Thin film magnetic alloy having low noise, high coercivity and high

A Co--Pt based magnetic alloy which has been sputtered with an oxide or nitride of a primary constituent of the magnetic layer, e.g., CoO below about 10 at. %, provides improved coercivity, squareness, and reduced noise as compared to magnetic alloys with oxygen introduced by other methods. The alloy is vacuum deposited, for example, by sputtering, and the oxide or nitride may be introduced from the sputtering target from which the magnetic layer materials come or from a separate sputtering target. Examples of such oxides and nitrides include CoO, Co.sub.2 0.sub.3, Co.sub.3 O.sub.4, CrO.sub.2, Cr.sub.2 O.sub.3, TiO.sub.2, Ta.sub.2 O.sub.5, Al.sub.2 O.sub.3, WO, CoN, Co.sub.2 N, TiN, TaN, CrN, NiN, etc.

Method of sputtering selected oxides and nitrides for forming magnetic

A new magnetic alloy exhibits high Hc and Ms while exhibiting excellent corrosion resistance, thereby providing ideal physical properties for high density recording applications. Other parameters of the media, such as SNR, PW50, and S are at least maintained, if not also improved. The alloy contains cobalt and up to 10 at. % Ni, up to 20 at. % Pt, up to 10 at. % Ta, up to 10 at. % Ti, and optionally up to 6 at. % B. The ratio of the tantalum to titanium in the alloy is between 3:1 and 1:3. The alloy is deposited by vacuum deposition (typically sputtering) on a similarly deposited non-magnetic alloy under layer. Nitrogen and/or oxygen may be introduced into the alloy during deposition to improve SNR. Other corrosion-resistant thin film alloys may also be obtained by the inclusion of Ta and Ti.

Magnetic alloy for improved corrosion resistance and magnetic performance

Thin film magnetic alloy having low noise, high coercivity, and high

A magnetic recording medium is provided with a structured nucleation layer. The structured nucleation layer comprises a fine-grained seed layer and an intermediate layer. The seed layer (e.g., NiAl, Ti, Cr--Cu, etc.) serves as a template for fine grained-growth of the intermediate layer. The intermediate (e.g., Cr, etc.) layer has preferred crystal textures and an appropriate lattice match to a subsequently deposited magnetic recording layer to allow epitaxial growth of the magnetic recording layer. The intermediate layer provides morphology and orientation to the magnetic recording layer. The magnetic recording layer (e.g., Co-alloy) includes a material which segregates to the alloy grain boundaries to isolate the grains thereof. Each grain of the magnetic recording layer is predominantly a single crystal of small size and uniformly spaced from adjacent grains. The easy axis of the magnetic recording material is predominantly in the plane of the disk, with a random in-plane orientation. Superior magnetic properties are obtained.

Magnetic alloy having a structured nucleation layer and method for

A Co--Pt based magnetic alloy which has been sputtered with an oxide or nitride of a primary constituent of the magnetic layer, e.g., CoO below about 10 at. %, provides improved coercivity, squareness, and reduced noise as compared to magnetic alloys with oxygen introduced by other methods. The alloy is vacuum deposited, for example, by sputtering, and the oxide or nitride may be introduced from the sputtering target from which the magnetic layer materials come or from a separate sputtering target. Examples of such oxides and nitrides include CoO, Co.sub.2 O.sub.3, Co.sub.3 O.sub.4, CrO.sub.2, Cr.sub.2 O.sub.3, TiO.sub.2, Ta.sub.2 O.sub.5, Al.sub.2 O.sub.3, WO, CoN, Co.sub.2 N, TiN, TaN, CrN, NiN, etc.

Method for forming an improved magnetic media including sputtering of

Definition of the required geometry of the air bearing surface ('ABS') of a magnetic head slider is achieved while providing an ABS which exhibits low wear, low friction, and low stiction at its interface with a disk surface, by securely embedding monocrystalline diamond particles into a lapping plate, removing substantially all particles from the plate which are not firmly affixed thereto, and lapping the slider in a linear, X-Y direction at a relatively high lapping pressure. Material susceptible to being dislodged during CSS is removed during the lapping process. Thus, the incidence of material dislodging from the ABS and increasing wear-induced stiction is substantially reduced, resulting in improved CSS performance. A desired microtexture is also applied to the ABS. Reduced pole tip recession is also observed.

CSS magnetic recording head slider and method of making same

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Monte Sereno, CA, United States of America

Tu Chen