US4785345A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Integrated transformer structure with primary winding in substrate
Assignee: AMERICAN TELEPHONE AND TELEGRAPH Co AT&T BELL LABS
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Filing: 1986-05-08
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Granted: 1988-11-15
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Expires: 2006-05-08
Abstract
Abstract An integrated transformer structure is disclosed. In one embodiment, the primary transformer winding is formed using dielectrically isolated (DI) technology so as to isolate high voltages applied to the transformer primary from other components in the substrate. Alternatively, conventional junction isolated technology may be used, where physical separation between the integrated transformer and other components may be provided. In accordance with the present invention, the primary winding comprises a planar spiral formed with a low-resistivity material and incorporated with the substrate. An insulating layer is then formed over the primary winding. A planar spiral configuration is also used to form the secondary winding, where the secondary may be formed of a deposited metal and is formed on top of the insulating layer so as to be directly above the primary winding. The result is an effective air-core transformer structure capable of isolating thousands of volts.
Inventors
- 👤 Spencer A. Rawls
- 👤 Luke J. Turgeon
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-01 22:58
CPC Classifications
H; H01; H01F; H01F27/00; H01F27/28; H01F27/2804; H01F17/00; H01F17/0006; H01R; H01R13/00; H01R13/648; H01R13/658; H01R13/6591; H01R13/65912; H01R13/6592; H01R13/6593; H01R13/6596; H10; H10W; H10W44/00; H10W44/501; H01F2017/0086; H01R13/02; H01R13/28; H01R13/62; H01R13/627; H01R13/73; H01R13/74; H01R2201/00; H01R2201/04; H01R2201/06
Claims Analysis
Total Claims: 13
Claim 1
Independent Claim
90 words
An integrated transformer structure comprising a semiconductor substrate of a first conductivity type defined as including top and bottom major surfaces; a primary winding comprising a planar spiral configuration of a low resistivity material formed in said top major surface of said substrate; an insulating region disposed to cover said top major surface including said primary winding; and a secondary winding comprising a planar spiral configuration of a low resistivity material formed over said insulating region in a manner such that said secondary winding is disposed above said primary winding.
Claim 2
Dependent Claim
90 words
An integrated transformer structure comprising a semiconductor substrate of a first conductivity type defined as including top and bottom major surfaces; a primary winding comprising a planar spiral configuration of a low resistivity material formed in said top major surface of said substrate; an insulating region disposed to cover said top major surface including said primary winding; and a secondary winding comprising a planar spiral configuration of a low resistivity material formed over said insulating region in a manner such that said secondary winding is disposed above said primary winding.
Claim 3
Dependent Claim
40 words
An integrated transformer structure as defined in claim 1 wherein the insulating region comprises a first insulating layer disposed to cover the top major surface of the substrate; and a second insulating layer disposed to cover said first insulating layer.
Claim 4
Dependent Claim
25 words
An integrated transformer structure as defined in claim 2 wherein the first insulating layer comprises silicon dioxide and the second insulating layer comprises phosphorous-doped silicon.
Claim 5
Dependent Claim
19 words
An integrated transformer structure as defined in claim 1 wherein the insulating region comprises a layer of silicon nitride.
Claim 6
Dependent Claim
29 words
An integrated transformer structure as defined in claims 1 or 2 wherein the primary winding spiral comprises a single turn and the secondary winding spiral comprises a single turn.
Claim 7
Dependent Claim
30 words
An integrated transformer structure as defined in claims 1 or 2 wherein the primary winding spiral comprises a single turn and the secondary winding spiral comprises more than one turn.
Claim 8
Dependent Claim
30 words
An integrated transformer structure as defined in claims 1 or 2 wherein the primary winding spiral comprises more than one turn and the secondary winding spiral comprises a single turn.
Claim 9
Dependent Claim
31 words
An integrated transformer structure as defined in claims 1 or 2 wherein the primary winding spiral comprises more than one turn and the secondary winding spiral comprises more than one turn.
Claim 10
Dependent Claim
19 words
An integrated transformer structure as defined in claims 1 or 2 wherein the primary winding material comprises n-doped polysilicon.
Claim 11
Dependent Claim
23 words
An integrated transformer structure as defined in claim 9 wherein a dielectric layer is utilized to separate the primary winding from the substrate.
Claim 12
Dependent Claim
18 words
An integrated transformer structure as defined in claims 1 or 2 wherein the secondary winding material comprises aluminum.
Claim 13
Dependent Claim
37 words
An integrated transformer structure as defined in claim 1 wherein the primary winding material comprises titanium and platinum, the insulating region comprises a layer of silicon nitride, and the secondary winding material comprises titanium, platinum, and gold.
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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) | 1991-11-15 | 1992-05-16 | 1992-11-15 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1995-11-15 | 1996-05-16 | 1996-11-15 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1999-11-15 | 2000-05-16 | 2000-11-15 | $7700.00 | Window Closed / Lapsed |