US4447290A
Expired / Lapsed
US
⏱️ 0.0 years remaining
CMOS Process with unique plasma etching step
Assignee: Intel Corp
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Filing: 1983-07-25
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Granted: 1984-05-08
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Expires: 2003-07-25
Abstract
Abstract A CMOS process which provides a self-aligned guardband in a high density circuit is disclosed. A polysilicon masking member is used to define a well and also to provide alignment for the guardband. A single plasma etching step etches silicon nitride in one area and both silicon nitride and polysilicon in another area prior to growth of field oxides.
Inventors
- 👤 James A. Matthews
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-28 15:31
CPC Classifications
H; H10; H10D; H10D84/00; H10D84/01; H10D62/00; H10D62/10; H10D62/102; H10D62/112; H10D84/0123; H10D84/0126; H10D84/0165; H10D84/0193; H10W; H10W10/00; H10W10/01; H10W10/011; H10W10/012; H10W10/0125; H10W10/0126; H10W10/0127; H10W10/10; H10W10/13
Claims Analysis
Total Claims: 2
Claim 1
Independent Claim
51 words
In the plasma etching of a polysilicon layer during the fabrication of an integrated circuit where SF 6 and O 2 are used for said etching, an improvement comprising: adding C n F m to said SF 6 and O 2 during said plasma etching to provide better end point detection.
Claim 2
Dependent Claim
51 words
In the plasma etching of a polysilicon layer during the fabrication of an integrated circuit where SF 6 and O 2 are used for said etching, an improvement comprising: adding C n F m to said SF 6 and O 2 during said plasma etching to provide better end point detection.
References Cited (Backward Citations)
US4330384A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1987-05-08 | 1987-11-07 | 1988-05-08 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1991-05-08 | 1991-11-07 | 1992-05-08 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1995-05-08 | 1995-11-07 | 1996-05-08 | $7700.00 | Window Closed / Lapsed |