IP Library Granted Patent US 7,153,441
Granted Patent B2
US 7,153,441 · App. 09/927,089 · Granted Dec 26, 2006

Method for manufacturing thin-film magnetic recording medium

View Patent ↗
Loading inventors, assignments & file history…
Monitor This Case
Get email alerts when status or documents change.
Order Certified Copies
Most orders are placed with the USPTO same day — all within 24 business hours.
Order via The Patent Place →
Pre-filled with this patent's details
Quick Facts
Patent No.
US 7,153,441
App. No.
09/927,089
Granted
Dec 26, 2006
Kind
B2
Abstract

A thin-film magnetic recording medium is produced by forming a laminate for magnetic data recording on a nonmagnetic substrate through a dry process, forming a protection layer on the laminate also through a dry process, plasma-etching the protection layer, and forming a lubricant layer on the plasma-etched protection layer. All steps are completed continuously in a vacuum without abrasion. The surface of the resulting recording medium is substantially smoother than the prior art.

Claims (22)

1. A method for manufacturing a thin-film magnetic recording medium, comprising the steps of:

forming a laminate for magnetic data recording on a nonmagnetic substrate;

said step of forming being a dry process in a vacuum atmosphere;

forming a protective layer on said laminate;

said step of forming a protective layer being a dry process in a vacuum atmosphere;

plasma-etching a first surface of said protective layer;

said step of plasma-etching conducted in a vacuum and in a process gas mixture comprising an inert gas, an oxygen gas, a nitrogen gas, and a gas selected from the group consisting of a chlorine gas and a fluorine gas, wherein particles on the entire surface of the protective layer are removed to make a smooth surface;

conducting the steps of forming a laminate, forming a protective layer, and plasma-etching, continuously; and

forming a lubricant layer on said first surface of said protective layer, whereby surface defects are minimized and surface quality is greatly improved.

2. A method, according to claim 1 , wherein:

said step of forming said laminate for magnetic data recording is at least one method selected from the group consisting of sputtering, ion plating, plasma CVD, and vacuum deposition.

3. A method, according to claim 2 , wherein:

said step of forming said protective layer is a method selected from the group consisting of sputtering, ion plating, plasma CVD, and vacuum deposition.

4. A method for manufacturing a thin-film magnetic recording medium, comprising the step of:

forming a laminate for magnetic data recording on a nonmagnetic substrate;

said step of forming being a dry process in a vacuum atmosphere;

forming a protective layer on said laminate;

said step of forming a protective layer being a dry process in a vacuum atmosphere;

plasma-etching a first surface of said protective layer;

said step of plasma-etching conducted in a vacuum and in a process gas mixture comprising an inert gas, an oxygen gas, a nitrogen gas, and a gas selected from the group consisting of a chlorine gas and a fluorine gas, wherein particles on the entire surface of the protective layer are removed to make a smooth surface;

conducting the steps of forming a laminate, forming a protective layer, and plasma-etching, continuously; and

forming a lubricant layer on said first surface of said protective layer, whereby surface defects are minimized and surface quality is greatly improved.

Assignments (5)
CHANGE OF NAME Recorded Oct 10, 2011
From: FUJI ELECTRIC DEVICE TECHNOLOGY CO., LTD.
To: FUJI ELECTRIC CO., LTD.
Reel/Frame 027249/0159 →
MERGER Recorded Oct 10, 2011
From: FUJI ELECTRIC DEVICE TECHNOLOGY CO., LTD. (MERGER)
To: FUJI ELECTRIC CO., LTD.
Reel/Frame 027288/0820 →
CHANGE OF NAME Recorded Jun 5, 2008
From: FUJI ELECTRIC CO., LTD.
To: FUJI ELECTRIC HOLDINGS CO., LTD.
Reel/Frame 021050/0015 →
ASSIGNMENT OF ASSIGNOR'S INTEREST Recorded Jun 5, 2008
From: FUJI ELECTRIC HOLDINGS CO., LTD.
To: FUJI ELECTRIC DEVICE TECHNOLOGY CO., LTD.
Reel/Frame 021050/0023 →
ASSIGNMENT OF ASSIGNOR'S INTEREST Recorded Oct 19, 2001
From: ISHIBASHI, SINICHI; IWAMA, TOSHINORI; TERASHIMA, EIJI; KUBOTA, MASAO; KOBAYASHI, YUJI
To: FUJI ELECTRIC CO., LTD.
Reel/Frame 012285/0526 →