EP0383570A2
Expired / Lapsed
EP
⏱️ 0.0 years remaining
Plasma etching method and apparatus
Assignee: Hitachi Ltd
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Filing: 1990-02-14
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Granted: —
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Expires: 2010-02-14
Abstract
Abstract In a plasma-etching method and apparatus for etching samples of e.g. semiconductor device substrates etc., a sample (24) is cooled and subjected to an etching process with a gas plasma. An acceleration voltage which accelerates ions in the gas plasma towards the sample (24) is repeatedly changed, e.g. by a controller (81). In a process based on low-temperature etching, an etching processing producing no residue, being anisotropic and being highly selective is realized.
Inventors
- 👤 Hironobu Kawahara
- 👤 Yoshinao Kawasaki
- 👤 Yoshiaki Sato
- 👤 Ryooji Fukuyama
Bibliographic Details
Application Number
—
Jurisdiction
EP
Data Source
google_patents
Last Synchronized
2026-10-30 07:41
CPC Classifications
H; H01; H01J; H01J37/00; H01J37/32; H01J37/32431; H01J37/32623; H01J37/32009; H01J37/32192; H01J37/3244; H01J37/32532; H01J37/32541; H01J37/32697; H01J37/32706; H01J37/32715; H01J37/32724; H01J37/32798; H01J37/32816; H01J37/32834; H10; H10P; H10P50/00; H10P50/20; H10P50/24; H10P50/242; H10P50/244; H10P50/26; H10P50/264; H10P50/266; H10P50/267; H10P72/00; H10P72/04; H10P72/0402; H10P72/0418; H10P72/0421; Y; Y10; Y10S; Y10S438/00; Y10S438/906
Claims Analysis
Total Claims: 14
Claim 1
Independent Claim
37 words
A plasma-etching method wherein a sample (24) is subjected to an etching process with a gas plasma, characterized in that an acceleration voltage for accelerating ions in said gas plasma toward said sample (24) is repeatedly changed.
Claim 2
Dependent Claim
37 words
A plasma-etching method wherein a sample (24) is subjected to an etching process with a gas plasma, characterized in that an acceleration voltage for accelerating ions in said gas plasma toward said sample (24) is repeatedly changed.
Claim 3
Dependent Claim
15 words
A plasma-etching method as defined in claim 1, wherein said acceleration voltage is periodically changed.
Claim 4
Dependent Claim
28 words
A plasma-etching method as defined in claim 1 or claim 2 wherein said acceleration voltage is formed of radio-frequency power which is supplied to a sample table (20).
Claim 5
Dependent Claim
29 words
A plasma-etching method as defined in claim 1 or claim 2, wherein said acceleration voltage is formed of a D.C. voltage which is supplied to a sample table (20).
Claim 6
Dependent Claim
35 words
A plasma-etching method as defined in claim 1 or claim 2, wherein said acceleration voltage is formed by synthesizing radio-frequency power and an A.C. voltage, the synthesized voltage being supplied to a sample table (20).
Claim 7
Dependent Claim
29 words
A plasma-etching method as defined in claim 1 or claim 2, wherein said acceleration voltage is formed of a D.C. voltage which is supplied to a grid electrode (87).
Claim 8
Dependent Claim
23 words
A plasma-etching method as defined in any one of claims 1 to 6 wherein said gas plasma is generated by microwave radiation (30).
Claim 9
Dependent Claim
28 words
A plasma-etching method as defined in any one of claims 1 to 6 wherein said gas plasma is generated by supplying radio-frequency power across parallel plate electrodes (20,93).
Claim 10
Dependent Claim
26 words
A plasma-etching method as defined in any one of claims 1 to 8 wherein said sample (24) is maintained at a temperature below 20°C during etching.
Claim 11
Dependent Claim
76 words
A plasma-etching method according to claim 1 comprising the steps of cooling a sample (24) to a temperature not higher than a water temperature, generating a gas plasma under a reduced pressure, and subjecting the cooled sample (24) to an etching process by the use of the gas plasma, characterized by supplying an acceleration voltage which accelerates ions in said gas plasma toward said sample (24), and repeatedly changing said acceleration voltage during said etching process.
Claim 12
Dependent Claim
38 words
Plasma-etching apparatus for carrying out a method as defined in any one of claims 1 to 10 characterized by means (80,81,81a,81b,83,86) for repeatedly changing an acceleration voltage which accelerates ions in said gas plasma toward said sample (24).
Claim 13
Dependent Claim
139 words
A plasma-etching apparatus for carrying out a method as defined in claim 1 having a vacuum vessel (10,14,90), evacuating means (60) for evacuating the vacuum vessel (10,14,90) so as to reduce the internal pressure thereof, gas supplying means (50) for supplying a processing gas into the vacuum vessel (10,14,90), plasma formation means (30,40,20,93,80) for converting the processing gas supplied into said vacuum vessel (10,14,90) to plasma, and cooling means (70) for cooling a sample table (20) disposed in the vacuum vessel (10,14,90) to a temperature not higher than a water temperature, characterized by voltage supplying means (80,83,86,87) for supplying an acceleration voltage which accelerates ions in the gas plasma towards a sample (24) which is arranged on said sample table, and control means (81,81a,8b) for repeatedly changing said acceleration voltage which is supplied by said voltage supplying means (80,83,86,87).
Claim 14
Dependent Claim
131 words
A plasma-etching apparatus for carrying out a method as defined in claim 1, having a vacuum vessel (10,14,90), evacuating means (60) for evacuating the vacuum vessel (10,14,90) so as to reduce the internal pressure thereof, gas supplying means (50) for supplying a processing gas into the vacuum vessel (10,14,90), plasma formation means (30,40,20,93,80) for converting the processing gas supplied into the vacuum vessel (10,14,90) to plasma, and cooling means (70) for cooling a sample table (20) disposed in the vacuum vessel (10,14,90) to a temperature not higher than a water temperature, characterized by bias supplying means (80,83,86) for supplying a bias voltage to said sample table (20), and control means (81,81a,81b) for repeatedly changing said bias voltage which is supplied to said sample table (20) by said bias supplying means (80,83,86).
References Cited (Backward Citations)
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