US5093753A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Magnetic reading head using the hall effect
Assignee: Thales SA
•
Filing: 1990-06-11
•
Granted: 1992-03-03
•
Expires: 2010-06-11
Abstract
Abstract Disclosed is a magnetic reading head using the Hall effect. In this head, the active element comprises a substrate on which the following are epitaxially grown: a layer of a semiconductor material with high electron mobility and a magnetic metallic multilayer formed by stacked layers of magnetic materials and non-magnetic materials, the layer of semiconductor material and the multilayer being electrically insulated from each other. This head also has electrodes for current supply and Hall voltage detection that are in contact with the layer of semiconductor material. The disclosed device can be applied to the reading of magnetic recording media.
Inventors
- 👤 Alain Friederich
- 👤 Gerard Creuzet
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-27 20:26
CPC Classifications
G; G11; G11B; G11B5/00; G11B5/127; G11B5/33; G11B5/37; G11B5/376; G11B5/378; H; H10; H10N; H10N52/00; H10N52/101
Claims Analysis
Total Claims: 16
Claim 1
Independent Claim
85 words
A magnetic reading head using the Hall effect, wherein the active element of the head comprises a substrate on which the following are epitaxially grown: a layer of a semiconductor material with high electron mobility and a magnetic metallic multilayer formed of substantially coextensive stacked layers of magnetic materials and non-magnetic materials, and electrodes for current supply and Hall voltage detection that are in contact with the layer of semiconductor material, the layer of semiconductor material and the multilayer being electrically insulated from each other.
Claim 2
Dependent Claim
85 words
A magnetic reading head using the Hall effect, wherein the active element of the head comprises a substrate on which the following are epitaxially grown: a layer of a semiconductor material with high electron mobility and a magnetic metallic multilayer formed of substantially coextensive stacked layers of magnetic materials and non-magnetic materials, and electrodes for current supply and Hall voltage detection that are in contact with the layer of semiconductor material, the layer of semiconductor material and the multilayer being electrically insulated from each other.
Claim 3
Dependent Claim
13 words
A reading head according to claim 1, wherein the multilayer has perpendicular anisotropy.
Claim 4
Dependent Claim
29 words
A reading head according to claim 1, wherein the non-magnetic material of the layers forming the multilayer is chosen from among chromium, silver or an alloy of these metals.
Claim 5
Dependent Claim
26 words
A reading head according to claim 1, wherein the non-magnetic material of the layers forming the multilayer is chosen from among cobalt or a cobalt alloy.
Claim 6
Dependent Claim
20 words
A reading head according to claim 1, wherein the multilayer has a thickness of between 100 Å and 1000 Å.
Claim 7
Dependent Claim
37 words
A reading head according to claim 1, wherein the semiconductor material with high electron mobility is chosen from among the compounds of the groups III and V of the periodic table of the elements such as GaAs.
Claim 8
Dependent Claim
19 words
A reading head according to claim 1, wherein the semiconductor material with high electron mobility consists of doped silicon.
Claim 9
Dependent Claim
25 words
A reading head according to claim 1, wherein the substrate is made of the same material as the semiconductor layer, but it is not doped.
Claim 10
Dependent Claim
26 words
A reading head according to claim 1, wherein the substrate, the layer of semiconductor material and the multilayer are made of materials having compatible lattice parameters.
Claim 11
Dependent Claim
21 words
A reading head according to claim 1, further comprising an insulating layer between the layer of semiconductor material and the multilayer.
Claim 12
Dependent Claim
28 words
A reading head according to claim 10, wherein the insulator layer is made of insulator oxide or of a semiconductor material with substantial gap height such as GaAlAs.
Claim 13
Dependent Claim
16 words
A reading head according to claim 1, wherein the multilayer is covered with a protection layer.
Claim 14
Dependent Claim
24 words
A reading head according to claim 12, wherein the protection layer is formed by a nitride-based layer or by an abrasion resistant non-magnetic layer.
Claim 15
Dependent Claim
22 words
A reading head according to claim 1, wherein at least the semiconductor layer and the multilayer are made by molecular beam epitaxy.
Claim 16
Dependent Claim
24 words
A multiple-track reading head, comprising several reading heads according to claim 1, made on a common substrate and separated from one another by etching.
References Cited (Backward Citations)
US4179719A
Cited
JPS5661022A
Cited
DE3126775A1
Cited
FR2578343A1
Cited
US4584552A
Cited
US4751598A
Cited
WO1986006878A1
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1995-03-03 | 1995-09-02 | 1996-03-03 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1999-03-03 | 1999-09-02 | 2000-03-03 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2003-03-03 | 2003-09-02 | 2004-03-03 | $7700.00 | Window Closed / Lapsed |