Patent US4412119A successfully refreshed from Google Patents.
US4412119A
Expired / Lapsed
US
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Method for dry-etching
Assignee: Hitachi Ltd
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Filing: 1981-05-05
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Granted: 1983-10-25
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Expires: 2001-05-05
Abstract
Abstract A dry-etching method for working SiO2, phospho-silicate glass, Si, Mo, W, Cr, TiW, Si3N4 or the like by the use of a glow discharge plasma involves the steps of introducing He, Ar, N2, O2 or a mixed gas thereof into a reaction chamber from the outside; and effecting the plasma discharge in the reaction chamber so that a reactive gas is liberated from a high molecular resin material arranged in the reaction chamber and containing fluorine atoms. The dry-etching method requires and uses no expensive gas containing a fluorocarbon, but has sufficient etching rate and selectivity.
Inventors
- 👤 Hideo Komatsu
- 👤 Shinya Iida
- 👤 Tatsumi Mizutani
- 👤 Kazuyoshi Ueki
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-25 19:09
CPC Classifications
H; H10; H10P; H10P50/00; H10P50/20; H10P50/26; H10P50/264; H10P50/266; H10P50/267; C; C23; C23F; C23F4/00; H10P50/24; H10P50/242; H10P50/268; H10P50/28; H10P50/282; H10P50/283
Claims Analysis
Total Claims: 17
Claim 1
Independent Claim
94 words
A drying-etching method for working the surface of a workpiece by the use of a glow discharge plasma comprising: a step of positioning a workpiece within a reaction chamber, a step (i) of introducing into said reaction chamber from the outside helium gas that is inactive with said workpiece even under a plasma discharge; and a step (ii) of effecting the plasma discharge in said reaction chamber so that a reactive gas that is reactive with said workpiece under the plasma discharge is liberated from a material which is arranged in said reaction chamber.
Claim 2
Dependent Claim
94 words
A drying-etching method for working the surface of a workpiece by the use of a glow discharge plasma comprising: a step of positioning a workpiece within a reaction chamber, a step (i) of introducing into said reaction chamber from the outside helium gas that is inactive with said workpiece even under a plasma discharge; and a step (ii) of effecting the plasma discharge in said reaction chamber so that a reactive gas that is reactive with said workpiece under the plasma discharge is liberated from a material which is arranged in said reaction chamber.
Claim 3
Dependent Claim
26 words
A dry-etching method according to claim 1, wherein said material arranged in said reaction chamber is made of a high molecular weight resin containing fluorine atoms.
Claim 4
Dependent Claim
41 words
A dry-etching method according to claim 2, wherein said high molecular weight resin is at least one resin selected from the group consisting of a polytetrafluoroethylene resin, a polymonochloratrifluoroethylene resin, a tetrafluoroethylenehexafluoropropylene copolymer resin, a polyvinylidenefluoride resin, and a polyvinylfluoride resin.
Claim 5
Dependent Claim
18 words
A dry-etching method according to claim 1, wherein said workpiece is made of SiO 2 or phospho-silicate glass.
Claim 6
Dependent Claim
32 words
A dry-etching method according to claim 1, wherein said workpiece is made of a substrate selected from the group consisting of Si, Mo, W, Cr, TiW and Si 3 N 4 .
Claim 7
Dependent Claim
29 words
A dry-etching method according to claim 1, wherein, at said step (ii), said inactive gas is continuously supplied to the inside of said reaction chamber during the plasma discharge.
Claim 8
Dependent Claim
34 words
A dry-etching method according to claim 1, wherein at said step (ii), said inactive gas is supplied to the inside of said reaction chamber only before and during the start-up of the plasma discharge.
Claim 9
Dependent Claim
20 words
A dry-etching method according to claim 1, wherein the gas pressure in said reaction chamber is 1.3 to 1330 Pa.
Claim 10
Dependent Claim
16 words
A dry-etching method according to claim 8, wherein said gas pressure is 13 to 133 Pa.
Claim 11
Dependent Claim
20 words
A dry-etching method according to claim 4, wherein the gas pressure in said reaction chamber is 20 to 50 Pa.
Claim 12
Dependent Claim
24 words
A dry-etching method according to claim 1, wherein the reactive gas liberated from the material arranged in the reaction chamber is a fluorine-containing gas.
Claim 13
Dependent Claim
33 words
A dry-etching method according to claim 1, wherein the plasma discharge is effected with a power density of 0.1 to 1 W/cm 2 and a power frequency of from 0.1 to 20 MHz.
Claim 14
Dependent Claim
52 words
A dry-etching method according to claim 4, wherein said workpiece is selectively covered with a photoresist, and whereby the ratio of etching rate of the SiO 2 of phospho-silicate glass to the etching rate of the photoresist is increased relative to the etching rate ratio when introducing argon gas in step (i).
Claim 15
Dependent Claim
63 words
A dry-etching method according to claim 13, wherein said workpiece is made of an SiO 2 or phospho-silicate glass layer on a silicon substrate, and whereby the ratio of the etching rate of the SiO 2 or phospho-silicate glass to the etching rate of the photoresist or silicon is increased relative to the etching rate ratio when introducing argon gas in step (i).
Claim 16
Dependent Claim
63 words
A dry-etching method according to claim 4, wherein said workpiece is made of an SiO 2 or phospho-silicate glass layer on a silicon substrate, and whereby the ratio of the etching rate of the SiO 2 or phospho-silicate glass to the etching rate of the photoresist or silicon is increased relative to the etching rate ratio when introducing argon gas in step (i).
Claim 17
Dependent Claim
18 words
A dry-etching method according to claim 4, 10, 13, 14 or 15, wherein said workpiece includes phospho-silicate glass.
References Cited (Backward Citations)
US4243476A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1986-10-24 | 1987-04-25 | 1987-10-25 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1990-10-24 | 1991-04-25 | 1991-10-25 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1994-10-24 | 1995-04-25 | 1995-10-25 | $7700.00 | Window Closed / Lapsed |