US5290361A
Expired / Lapsed
US
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Surface treating cleaning method
Assignee: Purex Co Ltd
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Filing: 1992-01-23
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Granted: 1994-03-01
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Expires: 2012-01-23
Abstract
Abstract A combination of a first surface treating solution comprising an inorganic or organic alkali such as ammonia or a quaternary ammonium hydroxide, hydrogen peroxide, water and a second surface treating solution of ultra-pure water, at least one of the first and second surface treating solutions containing as a complexing agent a compound having one or more phosphonic acid groups in the molecule and showing chelating ability, or an oxidized form thereof, or polyphosphoric acid or a salt thereof, is effective for making semiconductor surfaces free from harmful metallic impurities such as Fe, Al, Zn, etc.
Inventors
- 👤 Ichiro Hayashida
- 👤 Masahiko Kakizawa
- 👤 Kenichi Umekita
- 👤 Hiroyoshi Nawa
- 👤 Hisashi Muraoka
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-01 02:04
CPC Classifications
C; C11; C11D; C11D1/00; C11D1/66; C11D1/79; H; H10; H10P; H10P70/00; H10P70/10; H10P70/15; C01; C01B; C01B15/00; C01B15/01; C01B15/037; C11D3/00; C11D3/16; C11D3/36; C11D3/361; C11D3/364; C11D3/39; C11D3/3942; C11D7/00; C11D7/02; C11D7/04; C11D7/06; C11D7/10; C11D7/16
Claims Analysis
Total Claims: 9
Claim 1
Independent Claim
106 words
A process for treating semiconductor surfaces, which comprises a step of treating surfaces of semiconductors contaminated with metallic impurities including at least one of Fe, Al, Zn, Ca and Mg with a surface treating solution comprising an inorganic or organic alkali, hydrogen peroxide and water as major components, and a step of treating the resulting surface with ultra-pure water, at least one of the surface treating solution and the ultra-pure water containing as a complexing agent a compound having one or more phosphonic acid groups or a salt thereof and showing chelating ability or an oxidized form thereof, or a polyphosphoric acid or a salt thereof.
Claim 2
Dependent Claim
106 words
A process for treating semiconductor surfaces, which comprises a step of treating surfaces of semiconductors contaminated with metallic impurities including at least one of Fe, Al, Zn, Ca and Mg with a surface treating solution comprising an inorganic or organic alkali, hydrogen peroxide and water as major components, and a step of treating the resulting surface with ultra-pure water, at least one of the surface treating solution and the ultra-pure water containing as a complexing agent a compound having one or more phosphonic acid groups or a salt thereof and showing chelating ability or an oxidized form thereof, or a polyphosphoric acid or a salt thereof.
Claim 3
Dependent Claim
31 words
A process according to claim 1, wherein the complexing agent is contained in the surface treating solution and the concentration of Fe is reduced to 10 10 atoms/cm 2 or less.
Claim 4
Dependent Claim
30 words
A process according to claim 1, wherein the complexing agent is contained in the ultra-pure water and the concentration of Fe is reduced to 10 10 atoms/cm 2 or less.
Claim 5
Dependent Claim
19 words
A process according to claim 1, wherein the complexing agent is previously added to the inorganic or organic alkali.
Claim 6
Dependent Claim
16 words
A process according to claim 1, wherein the complexing agent is previously added to hydrogen peroxide.
Claim 7
Dependent Claim
67 words
A process according to claim 1, wherein the complexing agent is at least one member selected from the group consisting of methyl diphosphonic acid, aminotris(methylene phosphonic acid), ethylidene diphosphonic acid, 1-hydroxyethylidene-1,1-diphosphonic acid, 1-hydroxypropylidene-1,1,-diphosphonic acid, ethyl aminobis(methylene phosphonic acid), dodecyl aminobis(methylene phosphonic acid), nitrylotris(methylene phosphonic acid), ethylenediaminebis(methylene phosphonic acid), ethylenediamine-tetrakis(methylene phosphonic acid), hexenediamine-tetrakis(methylene phosphonic acid), diethylene-triaminepenta(methylene phosphonic acid), ammonium salts thereof, potassium salts thereof and lithium salts thereof.
Claim 8
Dependent Claim
38 words
A process according to claim 1, wherein the complexing agent is an N-oxide form obtained by oxidizing a compound having an N atom and one or more phosphonic acid groups or a salt thereof and showing chelating ability.
Claim 9
Dependent Claim
24 words
A process according to claim 1, wherein the complexing agent is contained in an amount of 10 -7 to 10 -3 % by weight.
References Cited (Backward Citations)
GB1119221A
Cited
GB1057089A
Cited
US4059678A
Cited
JPS50147284A
Cited
US4239661A
Cited
US4339340A
Cited
US4304762A
Cited
JPS5545484A
Cited
US4362706A
Cited
EP0097305A1
Cited
JPS5945601A
Cited
US4534945A
Cited
JPS60239305A
Cited
JPS6257567A
Cited
JPS6257566A
Cited
EP0276774A2
Cited
FR2624500A1
Cited
JPH05320377A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1997-02-28 | 1997-08-30 | 1998-03-01 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 2001-02-28 | 2001-08-30 | 2002-03-01 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2005-02-28 | 2005-08-30 | 2006-03-01 | $7700.00 | Window Closed / Lapsed |