Patent US5959522A successfully refreshed from Google Patents.
US5959522A
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US
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Integrated electromagnetic device and method
Assignee: Motorola Solutions Inc
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Filing: 1998-02-03
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Granted: 1999-09-28
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Expires: 2018-02-03
Abstract
Abstract An integrated electromagnetic device (112) provides increased inductance in a smaller area on a semiconductor substrate (130). A conduction path (140) is disposed on the substrate for developing the inductance. A first magnetic shield (142) is disposed between the substrate and the conduction path to concentrate the magnetic flux induced by current flowing along the conduction path, which increases the inductance. Inductance is further increased by shielding the magnetic flux from the substrate with the first magnetic shield, which reduces substrate eddy currents that oppose the applied current. A second magnetic shield (144) overlaying the conduction path is coupled to the first magnetic shield, further concentrating the magnetic flux and increasing the inductance.
Inventors
- 👤 James A. Andrews
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-31 18:44
CPC Classifications
H; H01; H01F; H01F17/00; H01F17/0006; H01F7/00; H01F7/06; H01F7/08
Claims Analysis
Total Claims: 14
Claim 1
Independent Claim
114 words
An electromagnetic device, comprising: a substrate; a conduction path overlaying the substrate and having first and second electrodes for developing an inductance of the electromagnetic device; a first magnetic shield disposed between the substrate and the conduction path wherein an opening is formed in the first magnetic shield and wherein the opening is suitable for running perpendicular to any applied current flow to reduce any eddy current within the first magnetic shield; and a second magnetic shield overlaying the conduction path and coupled to the first magnetic shield to enclose the conduction path wherein the first and second magnetic shields are suitable to increase magnetic fields generated by current flow along the conduction path.
Claim 2
Dependent Claim
114 words
An electromagnetic device, comprising: a substrate; a conduction path overlaying the substrate and having first and second electrodes for developing an inductance of the electromagnetic device; a first magnetic shield disposed between the substrate and the conduction path wherein an opening is formed in the first magnetic shield and wherein the opening is suitable for running perpendicular to any applied current flow to reduce any eddy current within the first magnetic shield; and a second magnetic shield overlaying the conduction path and coupled to the first magnetic shield to enclose the conduction path wherein the first and second magnetic shields are suitable to increase magnetic fields generated by current flow along the conduction path.
Claim 3
Dependent Claim
13 words
The electromagnetic device of claim 1, wherein the substrate comprises a semiconductor substrate.
Claim 4
Dependent Claim
16 words
The electromagnetic device of claim 2, wherein the electromagnetic device is formed on an integrated circuit.
Claim 5
Dependent Claim
42 words
The electromagnetic device of claim 1, wherein the conduction path is formed as a planar spiral and the opening is defined by first and second projections of the first magnetic shield that are disposed radially from an axis of the planar spiral.
Claim 6
Dependent Claim
52 words
The electromagnetic device of claim 4, wherein an opening of the second magnetic shield is defined by first and second projections of the second magnetic shield that are disposed radially from the axis of the planar spiral to reduce an eddy current in the second magnetic shield induced by the magnetic flux.
Claim 7
Dependent Claim
33 words
The electromagnetic device of claim 5, wherein the first and second magnetic shields are coupled for receiving a power supply voltage to maintain the first and second magnetic shields at a constant potential.
Claim 8
Dependent Claim
50 words
The electromagnetic device of claim 1, wherein the first and second magnetic shields are conductive, further comprising: a first dielectric layer disposed for electrically isolating the first magnetic shield from the conduction path; and a second dielectric layer disposed for electrically isolating the second magnetic shield from the conduction path.
Claim 9
Dependent Claim
20 words
The electromagnetic device of claim 1, wherein the electromagnetic device operates as an inductor, a transformer or a transmission line.
Claim 10
Dependent Claim
30 words
The electromagnetic device of claim 1, wherein the first magnetic shield has a relative permeability greater than 1.1 and the second magnetic shield has a relative permeability greater than 1.1.
Claim 11
Dependent Claim
19 words
The electromagnetic device of claim 9, wherein the first and second magnetic shields include iron, nickel, cobalt or permalloy.
Claim 12
Dependent Claim
67 words
An electromagnetic device, comprising: a semiconductor substrate; a conduction path overlaying the semiconductor substrate and having first and second electrodes for receiving an applied current to develop an inductance of the electromagnetic device; and a magnetic shield disposed between the semiconductor substrate and the conduction path and patterned with an opening that runs perpendicular to the applied current to reduce an eddy current in the semiconductor substrate.
Claim 13
Dependent Claim
67 words
An electromagnetic device, comprising: a semiconductor substrate; a conduction path overlaying the semiconductor substrate and having first and second electrodes for receiving an applied current to develop an inductance of the electromagnetic device; and a magnetic shield disposed between the semiconductor substrate and the conduction path and patterned with an opening that runs perpendicular to the applied current to reduce an eddy current in the semiconductor substrate.
Claim 14
Dependent Claim
41 words
The electromagnetic device of claim 9, wherein the conduction path is formed as a planar spiral and the opening is defined by first and second portions of the magnetic shield that are disposed radially from an axis of the planar spiral.
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 2002-09-27 | 2003-03-29 | 2003-09-28 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 2006-09-27 | 2007-03-29 | 2007-09-28 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2010-09-27 | 2011-03-29 | 2011-09-28 | $7700.00 | Window Closed / Lapsed |