Patent EP0258698A2 successfully refreshed from Google Patents.
EP0258698A2
Expired / Lapsed
EP
⏱️ 0.0 years remaining
Dry etching method
Assignee: Hitachi Ltd
•
Filing: 1987-08-12
•
Granted: —
•
Expires: 2007-08-12
Abstract
Abstract Etching of an article is carried out by maintaining the article at a temperature at which the vapor pressure of etching gas molecules becomes equal to or higher than the pressure of etching gas and the vapor pressure of neutral radicals contained in a plasma becomes equal to or lower than the pressure of an etching gas. An etching pattern with a substantially vertical side profile and extremely small in dimensional shift from the mask can be formed at high precision.
Inventors
- 👤 Sadayuki Okudaira
- 👤 Kazunori Tsujimoto
- 👤 Shinichi Tachi
Bibliographic Details
Application Number
—
Jurisdiction
EP
Data Source
google_patents
Last Synchronized
2026-10-30 23:03
CPC Classifications
H; H10; H10P; H10P50/00; H10P50/20; H10P50/24; H10P50/242; H10P50/26; H10P50/264; H10P50/266; H10P50/267; H10P50/268
Claims Analysis
Total Claims: 9
Claim 1
Independent Claim
97 words
A dry etching method in which the surface of an article is etched by contacting a plasma of an etching gas with said article surface, which comprises carrying out said etching by maintaining the temperature of said article above a temperature at which the vapor pressure of said etching gas molecules becomes equal to the pressure of said etching gas and below a temperature at which the vapor pressure of the reaction product produced from the reaction of neutral radicals contained in said plasma and said article surface becomes 10⁴ times the pressure of said etching gas.
Claim 2
Dependent Claim
97 words
A dry etching method in which the surface of an article is etched by contacting a plasma of an etching gas with said article surface, which comprises carrying out said etching by maintaining the temperature of said article above a temperature at which the vapor pressure of said etching gas molecules becomes equal to the pressure of said etching gas and below a temperature at which the vapor pressure of the reaction product produced from the reaction of neutral radicals contained in said plasma and said article surface becomes 10⁴ times the pressure of said etching gas.
Claim 3
Dependent Claim
41 words
The method of claim 1, wherein said article to be etched is maintained at a temperature at which the vapor pressure of said reaction product becomes 10³ times or less, preferably 10² times or less the pressure of said etching gas.
Claim 4
Dependent Claim
37 words
The method of claim 1, wherein said article to be etched is maintained at a temperature at which the vapor pressure of said reaction product becomes equal to or less than the pressure of said etching gas.
Claim 5
Independent Claim
20 words
The method of any of claims 1 to 3, wherein said etching is reactive ion etching, or microwave plasma etching.
Claim 6
Independent Claim
29 words
The method of any of claims 1 to 4, wherein said etching gas is at least one member selected from the group consisting of F₂, Cl₂, SF₆ and NF₃.
Claim 7
Independent Claim
44 words
The method of any of claims 1 to 4, wherein said article to be etched and said etching gas are tungsten and CF₄, respectively, and said article is maintained at a temperature in the range from -5°C to -160°C, preferably from -50°C to -160°C.
Claim 8
Independent Claim
47 words
The method of any of claims 1 to 4, wherein said article to be etched and said etching gas are silicon and SF₆, respectively, and said article to be etched is maintained at a temperature in the range from -95°C to -145°C, preferably from -130°C to -145°C.
Claim 9
Independent Claim
47 words
The method of any of claims 1 to 4, wherein said article to be etched and said etching gas are silicon and CF₄, respectively, and said article to be etched is maintained at a temperature in the range from -95°C to -190°C, preferably from -130°C to -190°C.
References Cited (Backward Citations)
No citation records indexed.
USPTO Annuity & Maintenance Windows
Maintenance schedule is calculated for granted US utility patents.