Patent US5476802A successfully refreshed from Google Patents.
US5476802A
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Method for forming an insulated gate field effect transistor
Assignee: Semiconductor Energy Laboratory Co Ltd
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Filing: 1994-05-27
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Granted: 1995-12-19
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Expires: 2014-05-27
Abstract
Abstract A method for forming an insulated gate field effect transistor capable of providing shorter channel lengths, said process comprising: forming on an insulator film having provided on a semiconductor, a portion for establishing a gate therewith in the later steps; introducing impurities into the semiconductor using said portion as the mask, to thereby establish a first impurity region in a self-aligned manner; establishing a gate by removing at least the sides of said portion by etching or by oxidizing a surface of said portion or by removing the oxidized surface; and introducing impurities into the semiconductor using said gate as the mask, to thereby establish a second impurity region in a self-aligned manner.
Inventors
- 👤 Shunpei Yamazaki
- 👤 Yasuhiko Takemura
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-30 20:01
CPC Classifications
H; H10; H10D; H10D86/00; H10D86/01; H10D30/00; H10D30/01; H10D30/021; H10D30/0223; H10D30/0227; H10D30/031; H10D30/0312; H10D30/0314; H10D30/0321
Claims Analysis
Total Claims: 18
Claim 1
Independent Claim
132 words
A method for forming an insulated gate field effect transistor having a gate electrode, comprising the steps of: forming a conductive material on an insulating film provided on a semiconductor; forming a first impurity region in said semiconductor by introducing an impurity into said semiconductor with said conductive material as a mask with an upper surface of said conductive material directly exposed to said impurity; removing a portion of said conductive material after forming the first impurity region in order to form a remaining portion thereof as said gate electrode; and forming a second impurity region in said semiconductor subsequent to said removing step by introducing an impurity into said semiconductor with said formed gate electrode as a mask with an upper surface of said gate electrode directly exposed to said impurity.
Claim 2
Independent Claim
132 words
A method for forming an insulated gate field effect transistor having a gate electrode, comprising the steps of: forming a conductive material on an insulating film provided on a semiconductor; forming a first impurity region in said semiconductor by introducing an impurity into said semiconductor with said conductive material as a mask with an upper surface of said conductive material directly exposed to said impurity; removing a portion of said conductive material after forming the first impurity region in order to form a remaining portion thereof as said gate electrode; and forming a second impurity region in said semiconductor subsequent to said removing step by introducing an impurity into said semiconductor with said formed gate electrode as a mask with an upper surface of said gate electrode directly exposed to said impurity.
Claim 3
Dependent Claim
24 words
The method of claim 1 wherein height of said gate electrode is more than one time as large as width of said gate electrode.
Claim 4
Dependent Claim
20 words
The method of claim 1 wherein said first impurity region has an impurity concentration higher than said second impurity region.
Claim 5
Dependent Claim
19 words
The method of claim 1 wherein said first impurity region forming step is carried out in a self-aligning manner.
Claim 6
Dependent Claim
19 words
The method of claim 1 wherein said second impurity region forming step is carried out in a self-aligning manner.
Claim 7
Dependent Claim
23 words
The method of claim 1 wherein said first impurity region has an impurity concentration of 1×10 20 to 5×10 21 cm -3 .
Claim 8
Dependent Claim
23 words
The method of claim 1 wherein said second impurity region has an impurity concentration of 1×10 17 to 5×10 18 cm -3 .
Claim 9
Independent Claim
107 words
A method for forming an insulated gate field effect transistor comprising the steps of: forming a pattern including a gate electrode therein on an insulating film provided on a semiconductor; forming a first impurity region in said semiconductor by introducing an impurity into said semiconductor with said pattern as a mask; oxidizing a portion of said pattern after forming said first impurity region; removing the oxidized portion in order to form a remaining portion thereof as said gate electrode; and forming a second impurity region in said semiconductor after removing said oxidized portion by introducing an impurity into said semiconductor with said gate electrode as a mask.
Claim 10
Independent Claim
107 words
A method for forming an insulated gate field effect transistor comprising the steps of: forming a pattern including a gate electrode therein on an insulating film provided on a semiconductor; forming a first impurity region in said semiconductor by introducing an impurity into said semiconductor with said pattern as a mask; oxidizing a portion of said pattern after forming said first impurity region; removing the oxidized portion in order to form a remaining portion thereof as said gate electrode; and forming a second impurity region in said semiconductor after removing said oxidized portion by introducing an impurity into said semiconductor with said gate electrode as a mask.
Claim 11
Dependent Claim
24 words
The method of claim 8 wherein height of said gate electrode is more than one time as large as width of said gate electrode.
Claim 12
Dependent Claim
20 words
The method of claim 8 wherein said first impurity region has an impurity concentration higher than said second impurity region.
Claim 13
Independent Claim
125 words
A method for forming an insulated gate field effect transistor comprising the steps of: forming a pattern including a gate electrode therein and comprising a polycrystal silicon on an insulating film provided on a single crystal silicon; forming a first impurity region in said single crystal silicon by introducing an impurity into said single crystal silicon with said pattern as a mask; oxidizing a portion of said pattern by thermal oxidation after forming said first impurity region; removing the oxidized portion in order to form a remaining portion thereof as said gate electrode; and forming a second impurity region in said single crystal silicon after removing said oxidized portion by introducing an impurity into said single crystal silicon with said gate electrode as a mask.
Claim 14
Independent Claim
125 words
A method for forming an insulated gate field effect transistor comprising the steps of: forming a pattern including a gate electrode therein and comprising a polycrystal silicon on an insulating film provided on a single crystal silicon; forming a first impurity region in said single crystal silicon by introducing an impurity into said single crystal silicon with said pattern as a mask; oxidizing a portion of said pattern by thermal oxidation after forming said first impurity region; removing the oxidized portion in order to form a remaining portion thereof as said gate electrode; and forming a second impurity region in said single crystal silicon after removing said oxidized portion by introducing an impurity into said single crystal silicon with said gate electrode as a mask.
Claim 15
Dependent Claim
24 words
The method of claim 11 wherein height of said gate electrode is more than one time as large as width of said gate electrode.
Claim 16
Dependent Claim
20 words
The method of claim 11 wherein said first impurity region has an impurity concentration higher than said second impurity region.
Claim 17
Independent Claim
118 words
A method for forming an insulated gate field effect transistor comprising the steps of: forming a conductive material on an insulating film provided on a semiconductor; forming a first impurity region in said semiconductor by introducing an impurity into said semiconductor with said conductive material as a mask with an upper surface of said conductive material directly exposed to said impurity; removing a portion of said conductive material by etching in order to form a remaining portion thereof as a gate electrode; and forming a second impurity region in said semiconductor by introducing an impurity into said semiconductor with said gate electrode as a mask with an upper surface of said gate electrode directly exposed to said impurity.
Claim 18
Independent Claim
118 words
A method for forming an insulated gate field effect transistor comprising the steps of: forming a conductive material on an insulating film provided on a semiconductor; forming a first impurity region in said semiconductor by introducing an impurity into said semiconductor with said conductive material as a mask with an upper surface of said conductive material directly exposed to said impurity; removing a portion of said conductive material by etching in order to form a remaining portion thereof as a gate electrode; and forming a second impurity region in said semiconductor by introducing an impurity into said semiconductor with said gate electrode as a mask with an upper surface of said gate electrode directly exposed to said impurity.
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