US4975324A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Perpendicular magnetic film of spinel type iron oxide compound and its manufacturing process
Assignee: Panasonic Holdings Corp
•
Filing: 1987-10-21
•
Granted: 1990-12-04
•
Expires: 2007-10-21
Abstract
Abstract Disclosed herein is a perpendicular magnetic film of spinel type iron oxide formed on a surface of a base substrate in the form of columnar grains which are densely arranged perpendicularly to the surface of the base substrate. A vapor of an organic iron compound or a mixed vapor consisting of the organic iron compound vapor and a vapor of an organic metal compound different from the organic iron compound is added with oxygen to obtain a mixed gas. The mixed gas is subjected to chemical vapor deposition on the substrate at low temperature, at reduced pressure in plasma, thereby to obtain the perpendicular magnetic film.
Inventors
- 👤 Hideo Torii
- 👤 Eiji Fujii
- 👤 Masaki Aoki
- 👤 Nobuyuki Aoki
- 👤 Keiichi Ochiai
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-04 21:13
CPC Classifications
G; G11; G11B; G11B5/00; G11B5/84; G11B5/85; C; C23; C23C; C23C16/00; C23C16/22; C23C16/30; C23C16/40; C23C16/406; C23C16/44; C23C16/50; C23C16/505; C23C16/507; G11B5/62; G11B5/64; G11B5/65; G11B5/658; Y; Y10; Y10S; Y10S428/00; Y10S428/90; Y10T; Y10T428/00; Y10T428/25; Y10T428/256; Y10T428/257
Claims Analysis
Total Claims: 10
Claim 1
Independent Claim
91 words
A perpendicular magnetic film formed on a surface of a base structure in the form of a columnar grains which are densely arranged perpendicularly to the surface of the base substrate, said film consisting of an iron oxide compound having a spinel crystal structure selected from the group consisting of γ-Fe 2 O 3 , Fe 3 O 4 and M x Fe 3-x O 4 , where M is a metal selected from the group consisting of Co, Ni, Mn and Zn and x is in the range of 0.25≦x≦1.0.
Claim 2
Dependent Claim
91 words
A perpendicular magnetic film formed on a surface of a base structure in the form of a columnar grains which are densely arranged perpendicularly to the surface of the base substrate, said film consisting of an iron oxide compound having a spinel crystal structure selected from the group consisting of γ-Fe 2 O 3 , Fe 3 O 4 and M x Fe 3-x O 4 , where M is a metal selected from the group consisting of Co, Ni, Mn and Zn and x is in the range of 0.25≦x≦1.0.
Claim 3
Dependent Claim
33 words
The perpendicular magnetic film according to claim 1, wherein the mean height-diameter ratio of the columnar grains is at least 6 and the column diameter of each grain is at most 450 Å.
Claim 4
Dependent Claim
51 words
A perpendicular magnetic film formed on a surface of a base substrate in the form of columnar grains which are densely arranged perpendicularly to the surface of the base substrate, said film consisting of γ-Fe 2 O 3 grown in the <111> direction perpendicularly to the surface of the base substrate.
Claim 5
Dependent Claim
51 words
A perpendicular magnetic film formed on a surface of a base substrate in the form of columnar grains which are densely arranged perpendicularly to the surface of the base substrate, said film consisting of γ-Fe 2 O 3 grown in the <111> direction perpendicularly to the surface of the base substrate.
Claim 6
Dependent Claim
33 words
The perpendicular magnetic film according to claim 3, wherein the mean height/diameter ratio of the columnar grains is at least 6 and the column diameter of each grain is at most 550 Å.
Claim 7
Dependent Claim
43 words
A perpendicular magnetic film formed on a surface of a base substrate in the form of columnar grains which are densely arranged perpendicularly to the surface of the base substrate, said film consisting of Co x Fe 3-x O 4 , where 0.3≦x≦1.0.
Claim 8
Dependent Claim
43 words
A perpendicular magnetic film formed on a surface of a base substrate in the form of columnar grains which are densely arranged perpendicularly to the surface of the base substrate, said film consisting of Co x Fe 3-x O 4 , where 0.3≦x≦1.0.
Claim 9
Dependent Claim
29 words
The perpendicular magnetic film according to claim 5, wherein Co x Fe 3-x O 4 is grown in the <100> direction perpendicularly to the surface of the base structure.
Claim 10
Dependent Claim
33 words
The perpendicular magnetic film according to claim 6, wherein the mean height/diameter ratio of the columnar grains is at least 6 and the column diameter of each grain is at most 450 Å.
References Cited (Backward Citations)
US3822210A
Cited
US4255492A
Cited
US4232071A
Cited
US4239835A
Cited
US4367263A
Cited
US4414271A
Cited
US4544612A
Cited
US4726988A
Cited
EP0169928A1
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1993-12-03 | 1994-06-04 | 1994-12-04 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1997-12-03 | 1998-06-04 | 1998-12-04 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2001-12-03 | 2002-06-04 | 2002-12-04 | $7700.00 | Window Closed / Lapsed |