Patent US3703110A successfully refreshed from Google Patents.
Patent US4819052A successfully refreshed from Google Patents.
US4819052A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Merged bipolar/CMOS technology using electrically active trench
Assignee: Texas Instruments Inc
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Filing: 1986-12-22
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Granted: 1989-04-04
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Expires: 2006-12-22
Abstract
Abstract Disclosed is a structure and method of fabricating bipolar and MOSFET devices isolated by an electrically active trench. A doped epitaxial layer (24) is formed on semiconductor substrate (10). A trench (36) is formed through the epitaxial layer (24) down to the substrate (10). The trench (36) is filled with a conductive material (54) and a topside contact (182) is formed in electrical contact with the conductive trench. A bipolar transistor (176) is formed in the epitaxial area (38) on one side of the trench (36) and a MOSFET transistor (178) is formed in the epitaxial area (40) on the other side of the trench (36). Plural contacts (200-206) can be made to the top surface of the trench (186), thereby maintaining the underlying substrate (10) at a desired and uniform potential.
Inventors
- 👤 Louis N. Hutter
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-28 12:33
CPC Classifications
H; H10; H10W; H10W10/00; H10D; H10D84/00; H10D84/01; H10D84/0107; H10D84/0109; H10D84/02; H10D84/03; H10D84/038; H10D84/40; H10D84/401; H10W10/01; H10W20/00; H10W20/01; H10W20/021
Claims Analysis
Total Claims: 25
Claim 1
Independent Claim
78 words
A semiconductor circuit comprising: a conductive substrate of a first conductivity type material; first and second semiconductor areas of a second conductivity type material formed on said substrate; a trench separating said first and second semiconductor areas, said trench including electrically isolating sidewalls and a bottom formed in said substrate; a conductive material filling said trench and in electrical contact with said substrate; and first and second semiconductor devices formed in respective said first and second semiconductor areas.
Claim 2
Dependent Claim
78 words
A semiconductor circuit comprising: a conductive substrate of a first conductivity type material; first and second semiconductor areas of a second conductivity type material formed on said substrate; a trench separating said first and second semiconductor areas, said trench including electrically isolating sidewalls and a bottom formed in said substrate; a conductive material filling said trench and in electrical contact with said substrate; and first and second semiconductor devices formed in respective said first and second semiconductor areas.
Claim 3
Dependent Claim
19 words
The semiconductor circuit of claim 1 wherein said trench sidewalls include electrical isolation comprising silicon nitride and silicon oxide.
Claim 4
Dependent Claim
21 words
The semiconductor circuit of claim 1 wherein said trench conductive material is doped with an impurity of said first conductivity type.
Claim 5
Dependent Claim
27 words
The semiconductor circuit of claim 1 wherein one of said semiconductor devices comprises a bipolar transistor and another of said semiconductor devices comprises a field effect transistor.
Claim 6
Dependent Claim
35 words
The semiconductor circuit of claim 4 further including a contact electrode formed in electrical contact with said conductive material filling said trench, and said electrode is connected to a ground node of said semiconductor circuit.
Claim 7
Dependent Claim
22 words
The semiconductor circuit of claim 1 further including a contact electrode formed in electrical contact with said conductivity material of said trench.
Claim 8
Dependent Claim
27 words
The semiconductor circuit of claim 6 further including a reference ground terminal of said semiconductor circuit, and wherein said contact electrode is connected to said ground terminal.
Claim 9
Dependent Claim
20 words
The semiconductor circuit of claim 1 wherein said trench is formed in a matrix enclosing a plurality of semiconductor areas.
Claim 10
Dependent Claim
36 words
The semiconductor circuit of claim 8 further including a plurality of electrical connections to the conductive material of said trench, said electrical connections being located on a trench surface opposite the connection thereto by said substrate.
Claim 11
Independent Claim
99 words
A method of fabricating a semiconductor circuit with a bipolar transistor isolated from a MOSFET transistor, comprising the steps of: forming a layer of semiconductor material of a first conductivity type on a substrate of second conductivity type; forming a trench through said layer of semiconductor material into contact with said substrate; forming an electrical isolation adjacent the sidewalls of said trench; filling said trench with a conductive material of said second conductivity type; and forming a bipolar transistor and a MOSFET transistor in said layer of semiconductor material, each said transistor formed on opposing sides of said trench.
Claim 12
Independent Claim
99 words
A method of fabricating a semiconductor circuit with a bipolar transistor isolated from a MOSFET transistor, comprising the steps of: forming a layer of semiconductor material of a first conductivity type on a substrate of second conductivity type; forming a trench through said layer of semiconductor material into contact with said substrate; forming an electrical isolation adjacent the sidewalls of said trench; filling said trench with a conductive material of said second conductivity type; and forming a bipolar transistor and a MOSFET transistor in said layer of semiconductor material, each said transistor formed on opposing sides of said trench.
Claim 13
Dependent Claim
30 words
The method of claim 10 further including forming a heavily doped buried layer of semiconductor material underlying said transistors and disposed between said layer of semiconductor material and said substrate.
Claim 14
Dependent Claim
21 words
The method of claim 10 further including forming said transistors with respective semiconductor regions contiguous with the sidewalls of said trench.
Claim 15
Dependent Claim
31 words
The method of claim 10 further including forming a semiconductor well of said second conductivity type in said layer of semiconductor material, and forming said MOSFET transistor in said semiconductor well.
Claim 16
Dependent Claim
18 words
The method claim 10 further including forming an external electrical contact to said conductive material of said trench.
Claim 17
Dependent Claim
17 words
The method of claim 14 further including forming a plurality of electrical contacts to said conductive material.
Claim 18
Dependent Claim
30 words
The method of claim 14 further including forming one of said transistor for carrying large currents, and forming said electrical contact to said trench proximate said transistor carrying large currents.
Claim 19
Dependent Claim
11 words
A semiconductor structure formed according to the method of claim 10.
Claim 20
Independent Claim
69 words
A method of providing multiple contacts to a substrate of a semiconductor circuit, comprising: forming a layer of semiconductor material on said substrate; forming a trench matrix through said semiconductor material into contact with said substrate; filling said trench matrix with a conductive material which is in electrical contact with said substrate; and forming a plurality of electrical contacts to said conductive material at locations remote from said substrate.
Claim 21
Independent Claim
69 words
A method of providing multiple contacts to a substrate of a semiconductor circuit, comprising: forming a layer of semiconductor material on said substrate; forming a trench matrix through said semiconductor material into contact with said substrate; filling said trench matrix with a conductive material which is in electrical contact with said substrate; and forming a plurality of electrical contacts to said conductive material at locations remote from said substrate.
Claim 22
Dependent Claim
20 words
The method of claim 18 and further including connecting each said electrical contact together, in order to reduce debiasing effects.
Claim 23
Dependent Claim
17 words
The method of claim 19 and further including connecting said plurality of contacts to a ground node.
Claim 24
Dependent Claim
20 words
The method of claim 18 and further including isolating said conductive material filling said trench matrix from said semiconductor material.
Claim 25
Dependent Claim
24 words
The method claim 21 and further including forming two transistor devices in said conductive material and isolated from one another by said trench matrix.
References Cited (Backward Citations)
US4672410A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1992-04-03 | 1992-10-03 | 1993-04-04 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1996-04-03 | 1996-10-03 | 1997-04-04 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2000-04-03 | 2000-10-03 | 2001-04-04 | $7700.00 | Window Closed / Lapsed |