Patent EP0180020A2 successfully refreshed from Google Patents.
EP0180020A2
Expired / Lapsed
EP
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Plasma etching system
Assignee: International Business Machines Corp
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Filing: 1985-09-17
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Granted: —
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Expires: 2005-09-17
Abstract
Abstract It has been discovered surprisingly that when a plasma is produced by exciting a gas or mixture of gages with microwaves and simultaneously also with a radio frequency electrical discharge, that the resulting plasma is much more highly chemically reactive than a plasma produced instead by only one of the excitations. Such a plasma etches a surface much faster than the sum of the etch rates produced by each of the excitations individually and the etching anisotropy may be controlled by varying the ration of the applied power of each of the two kinds of simultaneous excitation. Sample to be etched are mounted on electrode 30 within the reaction chamber 26 of the vessel 24, 28 and a RF field is established between the electrode and the base 36 by high frequency generator 50. A microwave cavity 10 loosely surrounds the vessel 24, 28 which is formed of material which is permeable to the frequency of the generator 14. A suitable plasma forming gas from source 32 flows through vessel 24,28 to vacuum pump 44. As the gas passes cavity 10 it is excited and forms a microwave plasma which impinges against the samples 46 and etches them. The RF field greatly enhances the rate of etching.
Inventors
- 👤 Michael Hatzakis
- 👤 Juri Rostyslav Paraszczak
- 👤 Bennett Robinson
Bibliographic Details
Application Number
—
Jurisdiction
EP
Data Source
google_patents
Last Synchronized
2026-10-30 17:26
CPC Classifications
H; H01; H01J; H01J37/00; H01J37/32; H01J37/32009; H01J37/32357; H05; H05H; H05H1/00; H05H1/24; H05H1/46
Claims Analysis
Total Claims: 12
Claim 1
Independent Claim
131 words
Apparatus for etching a material surface with a plasma, comprising: a reaction chamber (26) having an internal electrode (30) for supporting the material (46) to be etched; means (32, 44) for flowing a gas against the material surface to be etched: means (14) for exciting said flowing gas with microwave energy to form a flowing microwave plasma, said flowing microwave plasma being continuously excited by microwave energy as it flows against said material surface to be etched; and a high frequency power source (50) connected to said electrode for simultaneously exciting said microwave plasma flowing against said material surface to be etched with a radio frequency electric field, said radio frequency excitation enhancing the etching rate of said microwave plasma and making the etching effect of said microwave plasma more anisotropic.
Claim 2
Dependent Claim
131 words
Apparatus for etching a material surface with a plasma, comprising: a reaction chamber (26) having an internal electrode (30) for supporting the material (46) to be etched; means (32, 44) for flowing a gas against the material surface to be etched: means (14) for exciting said flowing gas with microwave energy to form a flowing microwave plasma, said flowing microwave plasma being continuously excited by microwave energy as it flows against said material surface to be etched; and a high frequency power source (50) connected to said electrode for simultaneously exciting said microwave plasma flowing against said material surface to be etched with a radio frequency electric field, said radio frequency excitation enhancing the etching rate of said microwave plasma and making the etching effect of said microwave plasma more anisotropic.
Claim 3
Dependent Claim
55 words
Apparatus as claimed in claim 1, wherein said means for flowing a gas against the material surface to be etched comprises; a source (32) of gas capable of being excited by microwave energy and by radio frequency energy; and a microwave permeable tube (24) for conveying gas from said gas source to said reaction chamber.
Claim 4
Dependent Claim
59 words
Apparatus as claimed in claim wherein said means for exciting said flowing gas comprises; an excited microwave cavity (10) through which said microwave permeable tube passes, a microwave plasma being formed within said cavity in said tube, said microwave plasma flowing within said tube from said cavity to said reaction chamber and against the material surface to be etched.
Claim 5
Dependent Claim
29 words
Apparatus as claimed in claim 3 wherein microwaves leak from said cavity, travel along said tube and propagate to the material surface to be etched in said reaction chamber.
Claim 6
Dependent Claim
24 words
Apparatus as claimed in claim 4 wherein the walls 28 of said reaction chamber facing the material surface to be etched are microwave permeable.
Claim 7
Dependent Claim
22 words
Apparatus as claimed in claim 5 wherein said microwave permeable tube (24) and said microwave permeable walls (25) are composed on quartz.
Claim 8
Dependent Claim
24 words
Apparatus as claimed in claim 2 wherein said means for flowing a gas further comprises a vacuum pump (44) connected to said reaction chamber.
Claim 9
Dependent Claim
17 words
Apparatus as claimed in claim 2 wherein said gas is a halogen or halocarbon or rare gas.
Claim 10
Dependent Claim
34 words
Apparatus as defined in claim 8 wherein said gas comprises a gas selected from the group consisting of 0 2t N 2 , H 2' CF 4 , C1 2 and SF 6 .
Claim 11
Independent Claim
89 words
A method for etching a material surface with a plasma, comprising the steps of: forming a microwave plasma; flowing the microwave plasma against the material surface to be etched, the microwave plasma being continuously excited with microwave energy while it flows against said surface to be etched; and simultaneously exciting said microwave plasma flowing against said surface to be etched with a radio frequency electric field, said radio frequency excitation enhancing the etching rate of said microwave plasma and making the etching effect of said microwave plasma more anisotropic.
Claim 12
Independent Claim
89 words
A method for etching a material surface with a plasma, comprising the steps of: forming a microwave plasma; flowing the microwave plasma against the material surface to be etched, the microwave plasma being continuously excited with microwave energy while it flows against said surface to be etched; and simultaneously exciting said microwave plasma flowing against said surface to be etched with a radio frequency electric field, said radio frequency excitation enhancing the etching rate of said microwave plasma and making the etching effect of said microwave plasma more anisotropic.
References Cited (Backward Citations)
No citation records indexed.
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