Tommy T Cheung

US Patent:

20130071693, Mar 21, 2013

Filed:

Sep 14, 2012

Appl. No.:

13/620110

Inventors:

Raj Thangaraj - Fremont CA, US
Huan Tang - Los Altos CA, US
Jing Gui - Fremont CA, US
John Wang - Fremont CA, US
Tommy T. Cheung - Alameda CA, US

Assignee:

SEAGATE TECHNOLOGY LLC - Cupertino CA

International Classification:

G11B 5/667

US Classification:

428828, 428827

Abstract:

A method of manufacturing a granular perpendicular magnetic recording medium with improved corrosion resistance comprises sequential steps of providing a non-magnetic substrate including a surface; forming a soft magnetic underlayer (SUL) over the surface; post-deposition heating the SUL; forming an intermediate layer stack over the heated SUL; and forming at least one granular, magnetically hard perpendicular magnetic recording layer over the intermediate layer stack. Heating of the SUL prior to formation of the intermediate layer stack results in formation of an intermediate layer stack with a smoother surface and a granular perpendicular recording layer with increased corrosion resistance than when SUL post-deposition heating is not performed.

US Patent:

20080170329, Jul 17, 2008

Filed:

Jan 11, 2007

Appl. No.:

11/651964

Inventors:

Raj Thangaraj - Fremont CA, US
Huan Tang - Los Altos CA, US
Jing Gui - Fremont CA, US
John Wang - Fremont CA, US
Tommy T. Cheung - Alameda CA, US

International Classification:

G11B 5/74

US Classification:

360131

Abstract:

A method of manufacturing a granular perpendicular magnetic recording medium with improved corrosion resistance comprises sequential steps of providing a non-magnetic substrate including a surface; forming a soft magnetic underlayer (SUL) over the surface; post-deposition heating the SUL; forming an intermediate layer stack over the heated SUL; and forming at least one granular, magnetically hard perpendicular magnetic recording layer over the intermediate layer stack. Heating of the SUL prior to formation of the intermediate layer stack results in formation of an intermediate layer stack with a smoother surface and a granular perpendicular recording layer with increased corrosion resistance than when SUL post-deposition heating is not performed.

US Patent:

20170069345, Mar 9, 2017

Filed:

Sep 9, 2015

Appl. No.:

14/848442

Inventors:

- Cupertino CA, US
Xiaoding Ma - Fremont CA, US
Paul M. Jones - Palo Alto CA, US
Hamid R. Samani - Los Altos CA, US
Tommy T. Cheung - Alameda CA, US
Christopher L. Platt - Fremont CA, US
Qian Guo - Fremont CA, US
Yang Yang - Fremont CA, US

International Classification:

G11B 5/725
C23C 16/56
C23C 16/48
C23C 16/26
G11B 5/84
C23C 16/50

Abstract:

Methods of forming a magnetic storage disc, the method including depositing a carbon containing material on a magnetic recording layer to form a carbon containing layer, wherein the carbon containing layer is deposited using chemical vapor deposition, ion beam deposition, or filtered cathodic arc deposition; treating the carbon containing layer with a source of oxygen to form an oxygen layer; and depositing a lubricant on the oxygen layer.