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US5804474A
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Method for forming a V-shaped gate electrode in a semiconductor device, and the structure of the electrode
Assignee: Murata Manufacturing Co Ltd
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Filing: 1997-04-04
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Granted: 1998-09-08
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Expires: 2017-04-04
Abstract
Abstract A method for forming a V-shaped gate electrode on a semiconductor substrate includes the following steps: A first gate opening is formed in a first resist between a source and a drain formed on a semiconductor substrate, and dummy openings are formed near both sides of the first gate opening. By baking the first resist, convex portions thereof which rise steeply are formed between the first gate opening and the dummy openings. A second resist is formed to overlay the first resist convex portions and the first gate opening. The second resist is removed from the first gate opening, and a second gate opening larger than the first gate opening is formed in the second resist above the first gate opening. Metal for the V-shaped gate electrode is deposited through the second gate opening on the sides of the first resist convex portions rising steeply from the bottom of the first gate opening. A lift-off technique is performed to leave the V-shaped gate electrode by dissolving the first resist convex portions and the second resist.
Inventors
- 👤 Hidehiko Sakaki
- 👤 Yasushi Yokoi
- 👤 Koji Monden
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-01 08:27
CPC Classifications
H; H10; H10D; H10D30/00; H10D30/01; H10D30/061; H10D30/0612; H10D64/00; H10D64/01; H10D64/012; H10D64/0124; H10D64/0125; H10P; H10P76/00; H10P76/20; H10P76/202; Y; Y10; Y10S; Y10S438/00; Y10S438/942; Y10S438/948; Y10S438/949; Y10S438/951
Claims Analysis
Total Claims: 11
Claim 1
Independent Claim
93 words
A method for forming a V-shaped gate electrode on a semiconductor substrate, comprising the steps of: forming a first resist covering said semiconductor substrate and a source and a drain formed thereon; forming a first gate opening in said first resist between said source and said drain on said semiconductor substrate; forming dummy openings in proximity to both sides of said first gate opening; and depositing metal on said semiconductor substrate, while utilizing said first gate opening and said dummy openings to guide said depositing of metal, to form said V-shaped gate electrode.
Claim 2
Independent Claim
93 words
A method for forming a V-shaped gate electrode on a semiconductor substrate, comprising the steps of: forming a first resist covering said semiconductor substrate and a source and a drain formed thereon; forming a first gate opening in said first resist between said source and said drain on said semiconductor substrate; forming dummy openings in proximity to both sides of said first gate opening; and depositing metal on said semiconductor substrate, while utilizing said first gate opening and said dummy openings to guide said depositing of metal, to form said V-shaped gate electrode.
Claim 3
Independent Claim
170 words
A method for forming a V-shaped gate electrode on a semiconductor substrate, comprising the steps of: forming a first gate opening on a first resist between a source and a drain formed on said semiconductor substrate, and forming dummy openings in proximity to both sides of said first gate opening; forming first resist convex portions rising steeply between said first gate opening and said dummy openings by baking said first resist; forming a second resist to overlay the first resist convex portions and said first gate opening; removing said second resist above said first gate opening, and forming a second gate opening larger than said first gate opening in said second resist above said first gate opening; depositing metal for said V-shaped gate electrode on the sides of the first resist convex portions rising steeply from the bottom of said first gate opening through said second gate opening; and performing a lift-off technique for leaving said V-shaped gate electrode by dissolving the first resist convex portions and said second resist.
Claim 4
Independent Claim
170 words
A method for forming a V-shaped gate electrode on a semiconductor substrate, comprising the steps of: forming a first gate opening on a first resist between a source and a drain formed on said semiconductor substrate, and forming dummy openings in proximity to both sides of said first gate opening; forming first resist convex portions rising steeply between said first gate opening and said dummy openings by baking said first resist; forming a second resist to overlay the first resist convex portions and said first gate opening; removing said second resist above said first gate opening, and forming a second gate opening larger than said first gate opening in said second resist above said first gate opening; depositing metal for said V-shaped gate electrode on the sides of the first resist convex portions rising steeply from the bottom of said first gate opening through said second gate opening; and performing a lift-off technique for leaving said V-shaped gate electrode by dissolving the first resist convex portions and said second resist.
Claim 5
Dependent Claim
65 words
A method for forming a V-shaped gate electrode according to claim 2, wherein said first gate opening, formed between a pair of said first resist convex portions after said first resist is baked, is shaped so that said gate electrode, formed by deposition of metal on the sides of the first resist convex portions from the bottom of said first gate opening, is generally V-shaped.
Claim 6
Dependent Claim
32 words
A method for forming a V-shaped gate electrode according to claim 3, wherein said second resist is baked at a temperature lower than a temperature at which said first resist is baked.
Claim 7
Dependent Claim
32 words
A method for forming a V-shaped gate electrode according to claim 2, wherein said second resist is baked at a temperature lower than a temperature at which said first resist is baked.
Claim 8
Dependent Claim
31 words
A method for forming a V-shaped gate electrode according to claim 1, wherein said gate electrode has a rise angle of 45 degrees or more with respect to said semiconductor substrate.
Claim 9
Dependent Claim
21 words
A method for forming a V-shaped gate electrode according to claim 6, wherein said rise angle is 65 degrees or more.
Claim 10
Dependent Claim
31 words
A method for forming a V-shaped gate electrode according to claim 2, wherein said gate electrode has a rise angle of 45 degrees or more with respect to said semiconductor substrate.
Claim 11
Dependent Claim
21 words
A method for forming a V-shaped gate electrode according to claim 8, wherein said rise angle is 65 degrees or more.
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