US5200361A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Process for preparing a semiconductor device using hydrogen fluoride and nitrogen to remove deposits
Assignee: Sharp Corp
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Filing: 1991-10-08
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Granted: 1993-04-06
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Expires: 2011-10-08
Abstract
Abstract A process for preparing a semiconductor device includes the steps of forming a lower wiring of aluminum or an aluminum alloy on a semiconductor substrate, coating said lower wiring with an interlayer dielectric film, forming via-holes in said interlayer dielectric film through a patterned resist by a reactive ion etching method, removing deposits produced by said method in said via-holes and a portion of said interlayer dielectric film around said deposits by means of hydrogen fluoride gas and nitrogen gas in the presence or absence of water vapor, and then forming an upper wiring on said interlayer dielectric film.
Inventors
- 👤 Shigeo Onishi
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-04 23:41
CPC Classifications
H; H10; H10P; H10P70/00; H10P70/20; H10P70/23; H10P70/234; H10P95/00; H10W; H10W20/00; H10W20/01; H10W20/071; H10W20/081; H10W20/082
Claims Analysis
Total Claims: 4
Claim 1
Independent Claim
116 words
A process for preparing a semiconductor device comprising the steps of forming a lower wiring of aluminum or an aluminum alloy on a semiconductor substrate, coating said lower wiring with an interlayer dielectric film, forming via-holes in said interlayer dielectric film through a patterned resist by a reactive ion etching method to expose said lower wiring, removing deposits produced by said method in said via-holes and a portion of said interlayer dielectric film around said deposits by means of a mixed gas of hydrogen fluoride gas and nitrogen gas at a ratio of hydrogen fluoride to nitrogen of 0.1-20 wt.% in the absence of water vapor, and then forming upper wiring on said interlayer dielectric film.
Claim 2
Dependent Claim
116 words
A process for preparing a semiconductor device comprising the steps of forming a lower wiring of aluminum or an aluminum alloy on a semiconductor substrate, coating said lower wiring with an interlayer dielectric film, forming via-holes in said interlayer dielectric film through a patterned resist by a reactive ion etching method to expose said lower wiring, removing deposits produced by said method in said via-holes and a portion of said interlayer dielectric film around said deposits by means of a mixed gas of hydrogen fluoride gas and nitrogen gas at a ratio of hydrogen fluoride to nitrogen of 0.1-20 wt.% in the absence of water vapor, and then forming upper wiring on said interlayer dielectric film.
Claim 3
Dependent Claim
29 words
A process as claimed in claim 1 wherein the interlayer dielectric film is an SiO 2 film formed by a plasma CVD method having a thickness of 0.5-1.5 μm.
Claim 4
Dependent Claim
42 words
A process as set forth in claim 1 wherein the reactive ion etching step produces deposits including an aluminum oxide and an aluminum halide, the step of removing the deposits including the step of removing the aluminum oxide and aluminum halide deposits.
References Cited (Backward Citations)
US4605479A
Cited
US4857142A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1996-04-05 | 1996-10-05 | 1997-04-06 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 2000-04-05 | 2000-10-05 | 2001-04-06 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2004-04-05 | 2004-10-05 | 2005-04-06 | $7700.00 | Window Closed / Lapsed |