EP0301335A2
Expired / Lapsed
EP
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Method of dry etching
Assignee: Hitachi Ltd
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Filing: 1988-07-15
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Granted: —
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Expires: 2008-07-15
Abstract
Abstract A first etching for large side etching is conducted while maintaining the temperature of the article to be etched at a first temperature, and a second etching for small side etching is then conducted while maintaining the article at a second temperature lower than the first temperature. This enables the formation of various patterns in which the upper part of the sidewall is inclined at a smaller angle than the lower part of the sidewall.
Inventors
- 👤 Shinichi Tachi
- 👤 Kazunori Tsujimoto
- 👤 Sakayuki Okudaira
Bibliographic Details
Application Number
—
Jurisdiction
EP
Data Source
google_patents
Last Synchronized
2026-10-30 10:30
CPC Classifications
H; H10; H10P; H10P50/00; H10P50/20; H10P50/26; H10P50/264; H10P50/266; H10P50/267; H10P50/268; H10P50/24; H10P50/242; H10P50/28; H10P50/282; H10P50/283
Claims Analysis
Total Claims: 11
Claim 1
Independent Claim
109 words
A method of dry etching comprising a first step of bringing an article to be etched placed within a reaction chamber into contact with a plasma of an etching gas while maintaining said article to be etched at a first temperature to etch the exposed surface of said article with a predetermined degree of a first side etching and a second step of bringing said article into contact with the plasma of said etching gas while maintaining said article at a second temperature different from the first temperature to etch said article with a degree of a second side etching different from the degree of the first side etching.
Claim 2
Independent Claim
109 words
A method of dry etching comprising a first step of bringing an article to be etched placed within a reaction chamber into contact with a plasma of an etching gas while maintaining said article to be etched at a first temperature to etch the exposed surface of said article with a predetermined degree of a first side etching and a second step of bringing said article into contact with the plasma of said etching gas while maintaining said article at a second temperature different from the first temperature to etch said article with a degree of a second side etching different from the degree of the first side etching.
Claim 3
Dependent Claim
33 words
The method of claim 1, wherein the second temperature is lower than the first temperature and the degree of the second side etching is smaller than the degree of the first side etching.
Claim 4
Dependent Claim
23 words
The method of claim 2, wherein a sidewall formed in the second step is substantially perpendicular to the main surface of said article.
Claim 5
Independent Claim
32 words
The method of any one of claims 1 to 3, wherein the first step is switched to the second step by stepwise or continuously varying the first temperature to the second temperature.
Claim 6
Independent Claim
30 words
The method of any one of claims 1 to 4, wherein said etching is conducted by making use of a plane-parallel plate dry etching apparatus or a plasma etching apparatus.
Claim 7
Independent Claim
24 words
The method of any one of claims 1 to 5, wherein the second temperature is by at least 10°C lower than the first temperature.
Claim 8
Independent Claim
30 words
The method of any one of claims 1 to 6, wherein said article to be etched is a film of aluminum and/or aluminum alloys and said etching gas is Cℓ₂.
Claim 9
Independent Claim
26 words
The method of any one of claims 1 to 6, wherein said article to be etched is a polysilicon film and said etching gas is SF₆.
Claim 10
Independent Claim
27 words
The method of any one of claims 1 to 6, wherein said article to be etched is a single-crystal silicon substrate and said etching as is SF₆.
Claim 11
Dependent Claim
34 words
The method of claim 9, wherein said dry etching forms a deep trench in which the upper part of the sidewall is inclined at a smaller angle than the lower part of the sidewall.
References Cited (Backward Citations)
No citation records indexed.
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