Patent US5770876A successfully refreshed from Google Patents.
US5770876A
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Semiconductor trench capacitor cell having a buried strap
Assignee: International Business Machines Corp
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Filing: 1996-11-13
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Granted: 1998-06-23
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Expires: 2016-11-13
Abstract
Abstract A semiconductor trench capacitor structure having a first level aligned insulation structure and buried strap that extends from within the trench into the semiconductor substrate. The semiconductor trench capacitor structure may be fabricated by forming a shallow trench extending into both the trench capacitor and the semiconductor substrate, depositing and densifying an insulating material within the shallow trench and using a resist layer to define and etch a strap trench aligned with the wall of the shallow trench, depositing a layer of conductive material within the strap trench and followed by depositing an insulating material therein.
Inventors
- 👤 Chung Hon Lam
- 👤 David K. Lord
- 👤 Judith A. Wright
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-30 03:26
CPC Classifications
H; H10; H10B; H10B12/00; H10B12/01; H10B12/02; H10B12/03; H10B12/038; H10B12/0385; H10D; H10D1/00; H10D1/01; H10D1/045; H10D1/047; H10D1/60; H10D1/62; H10D1/66; H10D1/665
Claims Analysis
Total Claims: 7
Claim 1
Independent Claim
126 words
A semiconductor structure comprising: a semiconductor substrate; a trench capacitor, said trench capacitor having an insulating layer and a conductive material situated therein; a buried strap recessed below a surface of said semiconductor substrate, said buried strap comprising a contiguous layer of conductive material extending into a section of said semiconductor substrate adjacent said trench capacitor and into a section of said trench capacitor; an upper insulation layer positioned above said buried strap; and a lower insulation layer positioned beneath and adjacent said buried strap, wherein said upper insulation layer and said lower insulation layer together form a planar surface and wherein a single edge of said buried strap is in electrical contact with said semiconductor substrate and with the conductive material of said trench capacitor.
Claim 2
Dependent Claim
126 words
A semiconductor structure comprising: a semiconductor substrate; a trench capacitor, said trench capacitor having an insulating layer and a conductive material situated therein; a buried strap recessed below a surface of said semiconductor substrate, said buried strap comprising a contiguous layer of conductive material extending into a section of said semiconductor substrate adjacent said trench capacitor and into a section of said trench capacitor; an upper insulation layer positioned above said buried strap; and a lower insulation layer positioned beneath and adjacent said buried strap, wherein said upper insulation layer and said lower insulation layer together form a planar surface and wherein a single edge of said buried strap is in electrical contact with said semiconductor substrate and with the conductive material of said trench capacitor.
Claim 3
Dependent Claim
17 words
The semiconductor structure of claim 1 wherein the bottom of said lower insulation layer is substantially planar.
Claim 4
Dependent Claim
13 words
The semiconductor structure of claim 1 wherein said buried strap comprises undoped polysilicon.
Claim 5
Dependent Claim
22 words
The semiconductor structure of claim 1 wherein said insulating material of said upper and lower insulation layers comprises a dense silicon oxide.
Claim 6
Dependent Claim
18 words
The semiconductor structure of claim 1 further comprising a dielectric layer over the surface of said semiconductor substrate.
Claim 7
Dependent Claim
22 words
The semiconductor structure of claim 5 wherein said dielectric layer comprises a layer of silicon nitride over a layer of silicon oxide.
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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) | 2001-06-22 | 2001-12-22 | 2002-06-23 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 2005-06-22 | 2005-12-22 | 2006-06-23 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2009-06-22 | 2009-12-22 | 2010-06-23 | $7700.00 | Window Closed / Lapsed |