Virgle Hedgcoth

50827472, Jan 21, 1992

Jan 12, 1990

7/464339

Virgle L. Hedgcoth - Pomona CA

H01F 100

428611

A magnetic thin film recording disk includes a substrate of a hard electroless plated nickel surface that has been textured to encourage a circular anisotropic orientation of crystal growth during a pass-by sputtering in a continuous production line. A thin film chromium nucleating layer that is substantially free of any oxidation that would affect the recording properties is subsequently deposited, and then a thin film magnetic layer of a cobalt alloy, having a desired circular anisotropic crystal growth, is deposited through the sputtering process. The resulting magnetic thin film recording disk is then coated with a thin film of a carbon protective material.

49580663, Sep 18, 1990

Aug 19, 1988

7/234394

Virgle L. Hedgcoth - Pomona CA

Secured Transactions - Pomona CA

G06K 1900

235487

A transactional instrument and method of producing the same is disclosed wherein a check can have a matrix array of subjectively coded symbols that are obscured from view, and which can be exposed in a particular manner for comparison with a dedicated ascertainable code to verify the transaction. Both the code and the addresses to the matrix array can be randomly generated, and removable opaque material can be used to obscure the coded symbols.

48941336, Jan 16, 1990

Jun 22, 1988

7/210119

Virgle L. Hedgcoth - Pomona CA

C23C 1434
B65H 100

20419215

A sputtering production assembly for producing a magnetic thin-film memory disk and a method of coating the memory disk is provided. The magnetic disk substrates are preliminarily abraded to provide a uniform series of physical circumferential texturing to encourage a circular anisotropic orientation of crystal growth during the subsequent sputtering steps. A nucleating layer is deposited under controlled conditions, and subsequently a thin-film magnetic layer is deposit with a circular anisotropic orientation of crystal growth. Finaly, a thin-film protective coating is disposed on the magnetic layer.

56269706, May 6, 1997

Jan 19, 1996

8/588617

Virgle L. Hedgcoth - Pomona CA

H01F 100
B32B 1504

428611

The improved sputtered memory disk of the present invention comprises a substrate coated with a nucleating layer, a subsequent magnetic layer, and a protective coating. As a result of texturing in the circumferential direction and epitaxy involving the nucleating layer, an anisotropic orientation of coercivity in the circumferential direction has occurred during the sputtering that provides an improved memory disk having enhanced coercivity, a reduced amplitude modulation, an improved squareness of the hysteresis loop, e. g. , lower switching field distribution, and a high production, relatively low cost production system. As a result, a higher recording density due to the higher coercivity and low switching field distribution can be experienced with the magnetic disk of the present invention.

50732455, Dec 17, 1991

Jul 10, 1990

7/550719

Virgle L. Hedgcoth - Pomona CA

C23C 1434

20429821

A magnetron sputtering device for coating planar substrates with sputtered ions. The sputtering occurs from the internal wall of a cylindrical hollow flanged cathode target that includes a slot longitudinally disposed in a sidewall of the cathode. A first portion of sputtered atoms travel through the slot and onto a planar substrate moving relative to the sputtering device and a second portion of sputtered atoms simply redeposit on the internal wall of the cathode target such that the target cathode evenly erodes.

60368241, Mar 14, 2000

May 5, 1997

8/851473

Virgle L. Hedgcoth - Pomona CA

Magnetic Media Development LLC - Manhattan Beach CA

C23C 1434

20419216

A process is provided for producing a thin-film magnetic longitudinal recording disk having a coercive anisotropy with a larger coercivity in a circumferential direction than in a radial direction of a disk. A substrate textured with circumferential grooves is provided. The textured substrate is then heated and a thin-film nucleating layer is sputtered above the textured substrate. Subsequently, a thin film magnetic layer of a hexagonal close-packed cobalt alloy is deposited above the nucleating layer.

47358408, Apr 5, 1988

Nov 12, 1985

6/796768

Virgle L. Hedgcoth - Pomona CA

Cyberdisk, Inc. - Anaheim CA

G11B 1000

428 65

The improved memory disk of the present invention comprises a substrate coated with chromium with preferably a layer of cobalt/nickel as the magnetic layer sealed with a protective coating of carbon. As a result of circumferential texturing, a circular anisotropic crystal growth has occurred during the sputtering with a circumferential alignment that provides an improved memory disk having a reduced amplitude modulation, an improved squareness of the hysteresis loop, e. g. lower switching field distribution and a high production relatively low cost production system. As a result, a higher recording linear bit density due to the high coercivity and low switching field distribution can be experienced with the magnetic disk of the present invention.

53168640, May 31, 1994

Jan 17, 1992

7/822589

Virgle L. Hedgcoth - Pomona CA

G11B 566
G11B 572
G11B 582

428611

A sputtered magnetic recording disk is formed by a series of sequential sputtering processes within an environment of a low pressure inert gas. A disk substrate is abraded to provide a circumferential texturing of hills and valleys. The height of the hills and valleys are of a dimension not to interfere with a fly characteristic of a recording head, while the arithmetic average of the radial roughness is still sufficient to provide a magnetic switching field distribution of less than 0. 20. A chromium nucleating layer is deposited on the textured substrate surface by a first sputtering process. A second sputtering process provide a magnetic layer of a cobalt alloy to provide C-axis orientation parallel to the substrate. A third sputtering process provides a protective carbon film. The output of any signal recorded on the magnetic thin film layer will have an amplitude modulation of less than twenty-five percent (25%).