US4582624A
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Etchant composition
Assignee: Daikin Industries Ltd
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Filing: 1984-08-09
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Granted: 1986-04-15
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Expires: 2004-08-09
Abstract
Abstract An aqueous etchant composition comprising hydrogen fluoride, ammonium fluoride and a surfactant selected from a group consisting of fluorine-containing carboxylic acids and their salts, with which very minute and complicated pattern can be etched onto an oxidized silicon film on a semiconductor substrate.
Inventors
- 👤 Naonori Enjo
- 👤 Koji Tamura
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-30 20:18
CPC Classifications
C; C23; C23F; C23F1/00; C23F1/10; C23F1/14; C23F1/16; C09; C09K; C09K13/00; C09K13/04; C09K13/08; H; H10; H10P; H10P50/00; H10P50/20; H10P50/28; H10P50/282; H10P50/283
Claims Analysis
Total Claims: 27
Claim 1
Independent Claim
102 words
An aqueous etchant composition comprising: (a) hydrogen fluoride and ammonium fluoride wherein the ratio of hydrogen fluoride and ammonium fluoride is at least 5 parts by weight of a 40% aqueous solution of ammonium fluoride added to about 1 part by weight of a 50% aqueous solution of hydrogen fluoride; and (b) a surfactant selected from a group consisting of fluorine-containing carboxylic acids and their salts, and said salts having a base of the formula: NR.sub.1 R.sub.2 R.sub.3 wherein R 1 , R 2 and R 3 are each hydrogen, C 1 -C 5 -alkyl or hydroxy --C 1 -C 5 -alkyl.
Claim 2
Dependent Claim
102 words
An aqueous etchant composition comprising: (a) hydrogen fluoride and ammonium fluoride wherein the ratio of hydrogen fluoride and ammonium fluoride is at least 5 parts by weight of a 40% aqueous solution of ammonium fluoride added to about 1 part by weight of a 50% aqueous solution of hydrogen fluoride; and (b) a surfactant selected from a group consisting of fluorine-containing carboxylic acids and their salts, and said salts having a base of the formula: NR.sub.1 R.sub.2 R.sub.3 wherein R 1 , R 2 and R 3 are each hydrogen, C 1 -C 5 -alkyl or hydroxy --C 1 -C 5 -alkyl.
Claim 3
Dependent Claim
31 words
The aqueous etchant composition according to claim 1, wherein the fluorine-containing carboxylic acid is of the formula: RfCOOH wherein Rf is a fluorine-containing hydrocarbon group having 3 to 20 carbon atoms.
Claim 4
Dependent Claim
28 words
The aqueous etchant composition according to claim 1, wherein the amount of the surfactant is from 0.0001 to 1% by weight based on the weight of the composition.
Claim 5
Dependent Claim
141 words
The aqueous etchant composition according to claim 1, wherein the surfactant is selected from the group consisting of CF 3 (CF 2 ) n COOH, (CF 3 ) 2 CF(CF 2 ) n COOH, HCF 2 (CF 2 ) n --COOH, CF 3 (CF 2 ) n (CH 2 ) m COOH, CF 3 (CF 2 ) n CF═CH(CH 2 ) m COOH and Cl(CF 2 CFCl) p CF 2 COOH wherein n is an integer of 2 to 17, m is 1 or 2 and p is an integer of 1 to 9, and their salts are NH 3 , (CH 3 ) 3 N, (C 2 H 5 ) 2 NH, C 3 H 8 NH 2 , NH 2 CH 2 CH 2 OH, NH(CH 2 CH 2 OH) 2 and N(CH 2 CH 2 OH) 3 .
Claim 6
Dependent Claim
13 words
The aqueous etchant composition according to claim 1, wherein the base is ammonia.
Claim 7
Dependent Claim
26 words
The aqueous etchant composition according to claim 1, wherein the amount of surfactant is from about 0.001-0.1% by weight based on the weight of the composition.
Claim 8
Dependent Claim
19 words
The aqueous etchant composition according to claim 1, wherein the hydrocarbon group has from 5 to 9 carbon atoms.
Claim 9
Dependent Claim
31 words
The aqueous etchant composition according to claim 1, wherein the fluorinated substituted carboxylic acid is further substituted with a substituent selected from the group consisting of chlorine, bromine, iodine and fluorine.
Claim 10
Dependent Claim
81 words
An aqueous etchant composition consisting essentially of: (a) hydrogen fluoride and ammonium fluoride, wherein the ratio of ammonium fluoride to hydrogen fluoride is at least 4 to 1 parts by weight; and (b) a surfactant selected from a group consisting of fluorine-containing carboxylic acids and their salts, said salts having a base of the formula: NR.sub.1 R.sub.2 R.sub.3 wherein R 1 , R 2 and R 3 are each hydrogen, C 1 -C 5 -alkyl or hydroxyl-C 1 -C 5 -alkyl.
Claim 11
Dependent Claim
81 words
An aqueous etchant composition consisting essentially of: (a) hydrogen fluoride and ammonium fluoride, wherein the ratio of ammonium fluoride to hydrogen fluoride is at least 4 to 1 parts by weight; and (b) a surfactant selected from a group consisting of fluorine-containing carboxylic acids and their salts, said salts having a base of the formula: NR.sub.1 R.sub.2 R.sub.3 wherein R 1 , R 2 and R 3 are each hydrogen, C 1 -C 5 -alkyl or hydroxyl-C 1 -C 5 -alkyl.
Claim 12
Dependent Claim
31 words
The aqueous etchant composition according to claim 9, wherein the fluorine-containing carboxylic acid is of the formula: RfCOOH wherein Rf is a fluorine-containing hydrocarbon group having 3 to 20 carbon atoms.
Claim 13
Dependent Claim
28 words
The aqueous etchant composition according to claim 9, wherein the amount of the surfactant is from 0.0001 to 1% by weight based on the weight of the composition.
Claim 14
Dependent Claim
13 words
The aqueous etchant composition according to claim 9, wherein the base is ammonia.
Claim 15
Dependent Claim
141 words
The aqueous etchant composition according to claim 9, wherein the surfactant is selected from the group consisting of CF 3 (CF 2 ) n COOH, (CF 3 ) 2 CF(CF 2 ) n COOH, HCF 2 (CF 2 ) n --COOH, CF 3 (CF 2 ) n (CH 2 ) m COOH, CF 3 (CF 2 ) n CF═CH(CH 2 ) m COOH and Cl(CF 2 CFCl) p CF 2 COOH wherein n is an integer of 2 to 17, m is 1 or 2 and p is an integer of 1 to 9, and their salts with NH 3 , (CH 3 ) 2 N, (C 2 H 5 ) 2 NH, C 3 H 8 NH 2 , NH 2 CH 2 CH 2 OH, NH(CH 2 CH 2 OH) 2 and N(CH 2 CH 2 OH) 3 .
Claim 16
Dependent Claim
26 words
The aqueous etchant composition according to claim 1, wherein the amount of surfactant is from about 0.001-0.1% by weight based on the weight of the composition.
Claim 17
Dependent Claim
19 words
The aqueous etchant composition according to claim 1, wherein the hydrocarbon group has from 5 to 9 carbon atoms.
Claim 18
Dependent Claim
31 words
The aqueous etchant composition according to claim 1, wherein the fluorinated substituted carboxylic acid is further substituted with a substituent selected from the group consisting of chlorine, bromine, iodine and fluorine.
Claim 19
Dependent Claim
76 words
A process for wet etching an oxidized silicon film, comprising etching the oxidized silicon film with an aqueous etchant composition which comprises hydrogen fluoride, ammonium fluoride and a surfactant selected from the group consisting of fluorine-containing carboxylic acids and their salts, said salts having a base of the formula: NR.sub.1 R.sub.2 R.sub.3 wherein R 1 , R 2 and R 3 are each hydrogen, C 1 -C 5 -alkyl or hydroxy C 1 -C 5 -alkyl.
Claim 20
Dependent Claim
76 words
A process for wet etching an oxidized silicon film, comprising etching the oxidized silicon film with an aqueous etchant composition which comprises hydrogen fluoride, ammonium fluoride and a surfactant selected from the group consisting of fluorine-containing carboxylic acids and their salts, said salts having a base of the formula: NR.sub.1 R.sub.2 R.sub.3 wherein R 1 , R 2 and R 3 are each hydrogen, C 1 -C 5 -alkyl or hydroxy C 1 -C 5 -alkyl.
Claim 21
Dependent Claim
31 words
The process according to claim 17, wherein the fluorine containing carboxylic acid is of the formula: RfCOOH wherein Rf is a fluorine containing hydrocarbon group having 3 to 20 carbon atoms.
Claim 22
Dependent Claim
27 words
The process according to claim 17, wherein the amount of the surfactant is from about 0.0001 to 1% by weight based on the weight of the composition.
Claim 23
Dependent Claim
11 words
The process according to claim 17, wherein the base is ammonia.
Claim 24
Dependent Claim
139 words
The process according to claim 17, wherein the surfactant is selected from the group consisting of CF 3 (CH 2 ) n COOH, (CF 3 ) 2 CF(CF 2 ) n COOH, HCF 2 (CF 2 ) n --COOH, CF 3 (CF 2 ) n (CH 2 ) m COOH, CF 3 (CF 2 ) n CF═CH(CH 2 ) m COOH and Cl(CF 2 CFCl) p CF 2 COOH wherein n is an integer of 2 to 17, m is 1 or 2 and p is an integer of 1 to 9, and their salts with NH 3 , (CH 3 ) 3 N, (C 2 H 5 ) 2 NH, C 3 H 8 NH 2 , NH 2 CH 2 CH 2 OH, NH(CH 2 CH 2 OH) 2 and N(CH 2 CH 2 OH) 3 .
Claim 25
Dependent Claim
24 words
The process according to claim 17, wherein the amount of surfactant is from about 0.001-0.1% by weight based on the weight of the composition.
Claim 26
Dependent Claim
17 words
The process according to claim 17, wherein the hydrocarbon group has from 5 to 9 carbon atoms.
Claim 27
Dependent Claim
29 words
The process according to claim 17, wherein the fluorinated substituted carboxylic acid is further substituted with a substituent selected from the group consisting of chlorine, bromine, iodine and fluorine.
References Cited (Backward Citations)
US4055458A
Cited
JPS5884974A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1989-04-14 | 1989-10-14 | 1990-04-15 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1993-04-14 | 1993-10-14 | 1994-04-15 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1997-04-14 | 1997-10-14 | 1998-04-15 | $7700.00 | Window Closed / Lapsed |