Patent US5560857A successfully refreshed from Google Patents.
US5560857A
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Solution for cleaning silicon semiconductors and silicon oxides
Assignee: Nippon Steel Corp
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Filing: 1994-10-11
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Granted: 1996-10-01
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Expires: 2014-10-11
Abstract
Abstract A cleaning solution for achieving highly accurate cleaning of silicon semiconductors and silicon oxides. The solution which enables a great reduction in the metal contaminants and the number of fine particles adhered on the surfaces and retention of the hydrophilic property of the surfaces to prevent the surfaces from being unstable, comprising an aqueous acidic solution containing 0.005% by weight or more to less than 0.05% by weight hydrogen fluoride and 0.3% by weight or more to 20.0% by weight or less hydrogen peroxide and having a pH in the range from 1 or more to less than 5.
Inventors
- 👤 Tadashi Sakon
- 👤 Kenichi Uemura
- 👤 Yoshihiro Mori
- 👤 Kengo Shimanoe
- 👤 Susumu Ohtsuka
- 👤 Shuji Munehira
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-05 08:59
CPC Classifications
H; H10; H10P; H10P70/00; H10P70/10; H10P70/15; Y; Y10; Y10S; Y10S438/00; Y10S438/906
Claims Analysis
Total Claims: 4
Claim 1
Independent Claim
56 words
A solution for cleaning silicon semiconductors and silicon oxides comprising an aqueous acidic solution containing 0.005% by weight or more to less than 0.05% by weight hydrogen fluoride and 0.3% by weight or more to 20.0% by weight or less hydrogen peroxide and having a pH in the range at least 1 to less than 5.
Claim 2
Dependent Claim
56 words
A solution for cleaning silicon semiconductors and silicon oxides comprising an aqueous acidic solution containing 0.005% by weight or more to less than 0.05% by weight hydrogen fluoride and 0.3% by weight or more to 20.0% by weight or less hydrogen peroxide and having a pH in the range at least 1 to less than 5.
Claim 3
Dependent Claim
31 words
The solution according to claim 1, wherein said aqueous acidic solution contains at least one selected from acids, salts and bases in addition to said hydrogen fluoride and said hydrogen peroxide.
Claim 4
Dependent Claim
61 words
The solution according to claim 2, wherein said acid is selected from the group consisting of phosphoric acid, sulfuric acid, nitric acid, trichloroacetic acid, dichloroacetic acid, hydrochloric acid, monochloroacetic acid and acetic acid, and said salt is selected from the group consisting of ammonium salts and amine salts, and the base is selected from the group consisting of ammonia and amines.
References Cited (Backward Citations)
JPS5222881A
Cited
US4171242A
Cited
JPH03228327A
Cited
EP0477504A1
Cited
EP0501492A2
Cited
JPH054811A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1999-10-01 | 2000-04-01 | 2000-10-01 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 2003-10-01 | 2004-04-01 | 2004-10-01 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2007-10-01 | 2008-04-01 | 2008-10-01 | $7700.00 | Window Closed / Lapsed |