Patent US6140169A successfully refreshed from Google Patents.
US6140169A
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Method for manufacturing field effect transistor
Assignee: Sony Corp
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Filing: 1999-04-01
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Granted: 2000-10-31
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Expires: 2019-04-01
Abstract
Abstract A GaN-type field effect transistor exhibits a large input amplitude by using a gate insulating film. A channel layer and a gate insulating film are sequentially laminated on a substrate with a buffer layer therebetween. A gate electrode is formed on the gate insulating film. A source electrode and a drain electrode are disposed at the both sides of the gate electrode and are electrically connected to the channel layer via openings. The channel layer is formed from n-type GaN. The gate insulating film is made from AlN, which exhibits excellent insulation characteristics, thus increasing the Schottky barrier and achieving a large input amplitude. If the FET is operated in the enhancement mode, it is operable in a manner similar to a Si-MOS-type FET, resulting in the formation of an inversion layer.
Inventors
- 👤 Hiroji Kawai
- 👤 Shunji Imanaga
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-25 15:02
CPC Classifications
H; H10; H10D; H10D64/00; H10D64/60; H10D64/66; H10D64/68; H10D64/693; H10D30/00; H10D30/01; H10D30/015; H10D30/021; H10D30/40; H10D30/47; H10D30/471; H10D30/472; H10D30/473; H10D30/4732; H10D30/475; H10D30/60; H10D62/00; H10D62/80; H10D62/85; H10D62/8503; H10D64/01; H10D64/012; H10D64/0124; H10D64/0125; H10D64/013; H10D64/01302; H10D64/01332; H10D64/01336; H10D64/01342
Claims Analysis
Total Claims: 14
Claim 1
Independent Claim
140 words
A manufacturing method for a field effect transistor of the type in which a source electrode and a drain electrode are disposed on a channel layer composed of a Group-III nitride compound semiconductor containing nitride and at least one of the Group-III elements selected from the group consisting of gallium (Ga), aluminum (Al), boron (B), and indium (In), and a gate electrode is formed on said channel layer with a gate insulating film therebetween, said method comprising the steps of: forming a gate-insulating-film forming layer after said channel layer is formed; forming a dummy gate, which serves as said gate electrode, on said gate-insulating-film forming layer; forming side walls on lateral surfaces of said dummy gate; and forming said gate insulating film by selectively removing said gate-insulating-film forming layer using said dummy gate and said side walls as a mask.
Claim 2
Dependent Claim
140 words
A manufacturing method for a field effect transistor of the type in which a source electrode and a drain electrode are disposed on a channel layer composed of a Group-III nitride compound semiconductor containing nitride and at least one of the Group-III elements selected from the group consisting of gallium (Ga), aluminum (Al), boron (B), and indium (In), and a gate electrode is formed on said channel layer with a gate insulating film therebetween, said method comprising the steps of: forming a gate-insulating-film forming layer after said channel layer is formed; forming a dummy gate, which serves as said gate electrode, on said gate-insulating-film forming layer; forming side walls on lateral surfaces of said dummy gate; and forming said gate insulating film by selectively removing said gate-insulating-film forming layer using said dummy gate and said side walls as a mask.
Claim 3
Dependent Claim
46 words
A manufacturing method according to claim 1, further comprising the step of forming said source electrode and said drain electrode on a contact layer, which is selectively formed on said channel layer by using said dummy gate and said side walls after said gate-insulating-film forming step.
Claim 4
Independent Claim
73 words
A method of manufacturing a field effect transistor, the method comprising the steps of: forming a channel layer on a substrate; forming a gate-insulating-film forming layer on the channel layer; forming a dummy gate on the gate-insulating-film forming layer; forming side walls on lateral surfaces of the dummy gate; and forming a gate insulating film by selectively removing the gate-insulating-film forming layer using the dummy gate and the side walls as a mask.
Claim 5
Independent Claim
73 words
A method of manufacturing a field effect transistor, the method comprising the steps of: forming a channel layer on a substrate; forming a gate-insulating-film forming layer on the channel layer; forming a dummy gate on the gate-insulating-film forming layer; forming side walls on lateral surfaces of the dummy gate; and forming a gate insulating film by selectively removing the gate-insulating-film forming layer using the dummy gate and the side walls as a mask.
Claim 6
Dependent Claim
22 words
The method of claim 3 further comprising the step of forming a buffer layer and an electron barrier layer on the substrate.
Claim 7
Dependent Claim
14 words
The method of claim 3 wherein the gate-insulating-film forming layer comprises an aluminum nitride.
Claim 8
Dependent Claim
49 words
The method of claim 3 wherein the step of forming a dummy gate on the gate-insulating-film forming layer is further defined by the steps of: laminating a silicon oxide layer on the gate-insulating-film forming layer; and partially removing the silicon oxide layer by etching to form the dummy gate.
Claim 9
Dependent Claim
51 words
The method of claim 3 wherein the step of forming side walls on lateral surfaces of the dummy gate is further defined by the steps of: laminating a silicon nitride layer on the dummy gate and the gate-insulating-film forming layer; and removing the silicon nitride layer to form the side walls.
Claim 10
Dependent Claim
47 words
The method of claim 3 wherein the step of forming the gate-insulating-film is further defined by the steps of: partially removing the gate-insulating-film forming layer by wet etching; and using the dummy gate and the side walls as an etching mask to form the gate insulating film.
Claim 11
Dependent Claim
18 words
The method of claim 3 further comprising the step of: forming a contact layer on the channel layer.
Claim 12
Dependent Claim
22 words
The method of claim 3 further comprising the step of: forming a source electrode and a drain electrode on the channel layer.
Claim 13
Dependent Claim
17 words
The method of claim 3 further comprising the step of: forming an insulating-film on the channel layer.
Claim 14
Dependent Claim
18 words
The method of claim 3 further comprising the step of: forming a gate electrode on the channel layer.
References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 2003-10-31 | 2004-05-01 | 2004-10-31 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 2007-10-31 | 2008-05-01 | 2008-10-31 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2011-10-31 | 2012-05-01 | 2012-10-31 | $7700.00 | Window Closed / Lapsed |