Patent US4549238A successfully refreshed from Google Patents.
US4549238A
Expired / Lapsed
US
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Magnetic head slider of ceramic material
Assignee: HGST Netherlands BV
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Filing: 1983-01-10
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Granted: 1985-10-22
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Expires: 2003-01-10
Abstract
Abstract A magnetic head slider consisting of a mixed ceramic made of aluminum oxide/titanium carbide has on its sliding side adjacent a magnetic record carrier a thin layer from which the titanium carbide component has been removed. The titanium carbide component preferably is removed by preferential reactive ion etching in a CF 4 plasma. The magnetic head slider with its sliding surface thus modified exhibits greatly improved sliding properties compared with sliders of the same material having a non-modified sliding surface.
Inventors
- 👤 Friedrich Ertingshausen
- 👤 Volker Heinrich
- 👤 Holger Hinkel
- 👤 Gerhard Kaus
- 👤 Jurgen Kempf
- 👤 Hans-Georg Nauth
- 👤 Manfred Schrader
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-07 15:21
CPC Classifications
G; G11; G11B; G11B5/00; G11B5/127; G11B5/187; G11B5/255; G11B23/00; G11B23/50; G11B23/505; G11B23/507; G11B5/10; G11B5/48; G11B5/58; G11B5/60; G11B5/6005
Claims Analysis
Total Claims: 9
Claim 1
Independent Claim
82 words
A magnetic head slider, particularly for magnetic heads flying on an air cushion over a moving magnetic data track, said slider having at least one surface containing a ceramic material including aluminum oxide and titanium carbide, characterized in that said surface is adapted to be adjacent the data track during operation and further characterized in that substantially all of the titanium carbide has been removed substantially to a preselected depth to create a series of isolated pits or recesses in said surface.
Claim 2
Dependent Claim
82 words
A magnetic head slider, particularly for magnetic heads flying on an air cushion over a moving magnetic data track, said slider having at least one surface containing a ceramic material including aluminum oxide and titanium carbide, characterized in that said surface is adapted to be adjacent the data track during operation and further characterized in that substantially all of the titanium carbide has been removed substantially to a preselected depth to create a series of isolated pits or recesses in said surface.
Claim 3
Dependent Claim
29 words
A magnetic head slider as claimed in claim 1, characterized in that the preselected depth to which the titanium carbide has been removed is between 10 and 100 nanometers.
Claim 4
Dependent Claim
26 words
A magnetic head slider as claimed in claim 1, characterized in that the preselected depth to which titanium carbide is removed is 20 to 50 nanometers.
Claim 5
Dependent Claim
25 words
A magnetic head slider as claimed in claim 1, characterized in that the ceramic material consists of approximately 70% aluminum oxide and 30% titanium carbide.
Claim 6
Dependent Claim
24 words
A magnetic head slider as claimed in claim 1, characterized in that the recesses result from removal of titanium carbide by reactive ion etching.
Claim 7
Dependent Claim
33 words
A magnetic head slider as claimed in claim 1, characterized in that the recesses result from removal of titanium carbide by preferential etching with reactive ion etching effected in a CF 4 plasma.
Claim 8
Independent Claim
89 words
A method of making a magnetic head slider of the type intended to fly over a moving magnetic disk, said slider having a surface that will be adjacent the magnetic disk during operation, and is formed of a ceramic material containing aluminum oxide and titanium carbide, comprising the step of removing the titanium carbide from said surface to a preselected depth by preferential reactive ion etching effected in a CF 4 plasma, thereby to create voids in said surface to increase the working lifetime of the slider and disk.
Claim 9
Independent Claim
89 words
A method of making a magnetic head slider of the type intended to fly over a moving magnetic disk, said slider having a surface that will be adjacent the magnetic disk during operation, and is formed of a ceramic material containing aluminum oxide and titanium carbide, comprising the step of removing the titanium carbide from said surface to a preselected depth by preferential reactive ion etching effected in a CF 4 plasma, thereby to create voids in said surface to increase the working lifetime of the slider and disk.
References Cited (Backward Citations)
US4251841A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1988-10-21 | 1989-04-22 | 1989-10-22 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1992-10-21 | 1993-04-22 | 1993-10-22 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1996-10-21 | 1997-04-22 | 1997-10-22 | $7700.00 | Window Closed / Lapsed |