Patent US5679589A successfully refreshed from Google Patents.
US5679589A
Expired / Lapsed
US
⏱️ 0.0 years remaining
FET with gate spacer
Assignee: Nokia of America Corp
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Filing: 1992-04-03
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Granted: 1997-10-21
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Expires: 2012-04-03
Abstract
Abstract A semiconductor integrated circuit structure and method of fabrication is disclosed. The structure includes a FET gate with adjacent double or triple layered gate spacers. The spacers permit precise tailoring of lightly doped drain junction profiles having deep and shallow junction portions. In addition, a self-aligned silicide may be formed solely over the deep junction portion thus producing a reliable low contact resistance connection to source and drain.
Inventors
- 👤 Kuo-Hua Lee
- 👤 Chih-Yuan Lu
- 👤 Janmye Sung
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-30 08:52
CPC Classifications
H; H10; H10D; H10D30/00; H10D30/01; H10D30/021; H10D30/0223; H10D30/0227; H10D30/60; H10D64/00; H10D64/01; H10D64/021
Claims Analysis
Total Claims: 5
Claim 1
Independent Claim
92 words
A method of semiconductor integrated circuit fabrication comprising: forming a gate stack over a substrate, said gate having a first overlying nitride layer; forming a first oxide layer upon said gate stack and selected portions of said substrate; depositing a second layer of nitride upon said first oxide layer; depositing a second oxide layer upon said second nitride layer; etching said second oxide layer to form a first spacer; etching said second nitride layer to form a second spacer underlying said first spacer; said first nitride layer remaining upon said gate stack.
Claim 2
Independent Claim
92 words
A method of semiconductor integrated circuit fabrication comprising: forming a gate stack over a substrate, said gate having a first overlying nitride layer; forming a first oxide layer upon said gate stack and selected portions of said substrate; depositing a second layer of nitride upon said first oxide layer; depositing a second oxide layer upon said second nitride layer; etching said second oxide layer to form a first spacer; etching said second nitride layer to form a second spacer underlying said first spacer; said first nitride layer remaining upon said gate stack.
Claim 3
Dependent Claim
54 words
The method of claim 1 further including the steps of forming at least two junctions in said substrate; depositing a conductive material upon said substrate and upon at least one gate stack, said gate stack having said first nitride layer upon it, said conductive material contacting both of said junctions; patterning said conductive material.
Claim 4
Dependent Claim
25 words
The method of claim 2 wherein said conductive material is chosen from the group consisting of polysilicon, aluminum, tungsten, titanium, tantalum, metal silicide, or molybdenum.
Claim 5
Dependent Claim
59 words
The method of claim 1 which said step of forming a gate stack includes: growing an oxide layer upon said substrate; depositing a polysilicon layer on said oxide layer; depositing a nitride layer upon said polysilicon layer; and etching said oxide layer, said polysilicon layer, and said nitride layer to form said gate stack having an overlying nitride layer.
References Cited (Backward Citations)
EP0083783A2
Cited
JPS58158970A
Cited
US4503601A
Cited
JPS59220971A
Cited
JPS60241267A
Cited
US4727038A
Cited
JPS61101077A
Cited
US4740484A
Cited
EP0197738A2
Cited
US4843023A
Cited
EP0218408A2
Cited
US4701423A
Cited
US4703551A
Cited
US4735680A
Cited
JPS6437852A
Cited
US4755478A
Cited
US4818714A
Cited
US4885259A
Cited
US4877755A
Cited
JPH023242A
Cited
US5015598A
Cited
US4981810A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 2000-10-20 | 2001-04-21 | 2001-10-21 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 2004-10-20 | 2005-04-21 | 2005-10-21 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2008-10-20 | 2009-04-21 | 2009-10-21 | $7700.00 | Window Closed / Lapsed |