US5899709A
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Method for forming a semiconductor device using anodic oxidation
Assignee: Semiconductor Energy Laboratory Co Ltd
•
Filing: 1996-04-03
•
Granted: 1999-05-04
•
Expires: 2016-04-03
Abstract
Abstract An improved method for manufacturing an insulated gate field effect transistor is described. The method comprises the steps of forming a semiconductor film on an insulating substrate, forming a gate insulating film on said semiconductor film, forming a gate electrode on said gate insulating film with said gate insulating film inbetween, anoding said gate electrode in order to coat an external surface of said gate electrode with an oxide film thereof and applying a negative or positive voltage to said gate electrode with respect to said semiconductor film. Lattice defects and interfacial states caused by the application of a positive voltage during the anoding are effectively eliminated by the negative voltage application.
Inventors
- 👤 Shunpei Yamazaki
- 👤 Hongyong Zhang
- 👤 Hideki Uochi
- 👤 Hiroki Adachi
- 👤 Yasuhiko Takemura
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-06 14:56
CPC Classifications
H; H10; H10D; H10D86/00; H10D86/01; H10D86/021; H10D30/00; H10D30/01; H10D30/021; H10D30/031; H10D30/0312; H10D30/0314; H10D30/0316; H10D30/0321; H10D30/60; H10D30/67; H10D30/6729; H10D30/6737; H10D30/6739; H10D86/40; H10D86/60; H10P; H10P14/00; H10P14/60; H10P14/63; H10P14/6302; H10P14/6304; H10P14/6306; H10P14/6308
Claims Analysis
Total Claims: 33
Claim 1
Independent Claim
84 words
A method for manufacturing a semiconductor device having at least a insulating film on a substrate comprising steps of: preparing a wiring, said wiring comprising an anodizable conductive material and contacting with said insulating film; putting said wiring into an electrolyte; and applying a voltage to said wiring in said electrolyte in order to form an anodic oxide film on a surface of said wiring and reform said insulating film, wherein said voltage is a D.C. voltage to which an alternating voltage is superposed.
Claim 2
Independent Claim
84 words
A method for manufacturing a semiconductor device having at least a insulating film on a substrate comprising steps of: preparing a wiring, said wiring comprising an anodizable conductive material and contacting with said insulating film; putting said wiring into an electrolyte; and applying a voltage to said wiring in said electrolyte in order to form an anodic oxide film on a surface of said wiring and reform said insulating film, wherein said voltage is a D.C. voltage to which an alternating voltage is superposed.
Claim 3
Dependent Claim
20 words
The method of claim 1 wherein an amplitude of said alternating voltage is 20 to 50% of said D.C. voltage.
Claim 4
Dependent Claim
19 words
A method according to claim 1 wherein a frequency of said alternating voltage is from 1 to 10 Hz.
Claim 5
Independent Claim
84 words
A method for forming an insulated gate field effect transistor comprising the steps of: forming a semiconductor film on a substrate; forming source and drain regions in said semiconductor film; forming a gate insulating film on said semiconductor region; forming a gate electrode on said gate insulating film; forming an oxide film on a surface of said gate electrode by applying a voltage to said gate electrode in an electrolyte, wherein said voltage is a D.C. voltage to which an alternating voltage is superposed.
Claim 6
Independent Claim
84 words
A method for forming an insulated gate field effect transistor comprising the steps of: forming a semiconductor film on a substrate; forming source and drain regions in said semiconductor film; forming a gate insulating film on said semiconductor region; forming a gate electrode on said gate insulating film; forming an oxide film on a surface of said gate electrode by applying a voltage to said gate electrode in an electrolyte, wherein said voltage is a D.C. voltage to which an alternating voltage is superposed.
Claim 7
Dependent Claim
20 words
The method of claim 4 wherein, an amplitude of said alternating voltage is 20 to 50% of said D.C. voltage.
Claim 8
Dependent Claim
19 words
A method according to claim 4 wherein a frequency of said alternating voltage is from 1 to 10 Hz.
Claim 9
Independent Claim
74 words
A method for forming an insulated gate field effect transistor comprising the steps of: forming a gate electrode on a substrate; forming an oxide film on a surface of said gate electrode by applying a voltage including an alternating voltage to said gate electrode in an electrolyte; forming a gate insulating film on said oxide film; forming a semiconductor film on said gate insulating film; forming source and drain regions in said semiconductor film.
Claim 10
Independent Claim
74 words
A method for forming an insulated gate field effect transistor comprising the steps of: forming a gate electrode on a substrate; forming an oxide film on a surface of said gate electrode by applying a voltage including an alternating voltage to said gate electrode in an electrolyte; forming a gate insulating film on said oxide film; forming a semiconductor film on said gate insulating film; forming source and drain regions in said semiconductor film.
Claim 11
Dependent Claim
19 words
The method of claim 7 wherein said voltage is generated by superposing said alternating voltage on a direct voltage.
Claim 12
Dependent Claim
19 words
A method according to claim 7 wherein a frequency of said alternating voltage is from 1 to 10 Hz.
Claim 13
Independent Claim
83 words
A method for forming an insulated gate field effect transistor comprising the steps of: forming a gate electrode on a substrate; forming an oxide film on a surface of said gate electrode by applying a voltage including an alternating voltage to said gate electrode in an electrolyte; forming a gate insulating film on said oxide film; forming a semiconductor film on said gate insulating film, said semiconductor film having a channel region therein; and forming source and drain regions on said semiconductor film.
Claim 14
Independent Claim
83 words
A method for forming an insulated gate field effect transistor comprising the steps of: forming a gate electrode on a substrate; forming an oxide film on a surface of said gate electrode by applying a voltage including an alternating voltage to said gate electrode in an electrolyte; forming a gate insulating film on said oxide film; forming a semiconductor film on said gate insulating film, said semiconductor film having a channel region therein; and forming source and drain regions on said semiconductor film.
Claim 15
Dependent Claim
19 words
The method of claim 10 wherein said voltage is generated by superposing said alternating voltage on a direct voltage.
Claim 16
Dependent Claim
19 words
The method of claim 10 wherein said voltage is generated by superposing said alternating voltage on a direct voltage.
Claim 17
Dependent Claim
19 words
A method according to claim 10 wherein a frequency of said alternating voltage is from 1 to 10 Hz.
Claim 18
Independent Claim
68 words
A method for forming an insulated gate field effect transistor comprising the steps of: forming source and drain regions on a substrate; forming a semiconductor film on said source/drain regions and said substrate; forming a gate electrode on said gate insulating film; forming an oxide film on a surface of said gate electrode by applying a voltage including an alternating voltage to said gate electrode in an electrolyte.
Claim 19
Independent Claim
68 words
A method for forming an insulated gate field effect transistor comprising the steps of: forming source and drain regions on a substrate; forming a semiconductor film on said source/drain regions and said substrate; forming a gate electrode on said gate insulating film; forming an oxide film on a surface of said gate electrode by applying a voltage including an alternating voltage to said gate electrode in an electrolyte.
Claim 20
Dependent Claim
19 words
The method of claim 14 wherein said voltage is generated by superposing said alternating voltage on a direct voltage.
Claim 21
Dependent Claim
19 words
A method according to claim 14 wherein a frequency of said alternating voltage is from 1 to 10 Hz.
Claim 22
Independent Claim
81 words
A method for forming an insulated gate field effect transistor comprising the steps of: forming a semiconductor film on a substrate; forming source and drain regions in said semiconductor film; forming a gate insulating film on said semiconductor region; forming a gate electrode on said gate insulating film; forming an oxide film on a surface of said gate electrode by applying a voltage to said gate electrode in an electrolyte, wherein said voltage is a D.C. voltage containing an A.C. component.
Claim 23
Independent Claim
81 words
A method for forming an insulated gate field effect transistor comprising the steps of: forming a semiconductor film on a substrate; forming source and drain regions in said semiconductor film; forming a gate insulating film on said semiconductor region; forming a gate electrode on said gate insulating film; forming an oxide film on a surface of said gate electrode by applying a voltage to said gate electrode in an electrolyte, wherein said voltage is a D.C. voltage containing an A.C. component.
Claim 24
Dependent Claim
18 words
A method according to claim 17 wherein said A.C. component has a frequency of 1 to 10 Hz.
Claim 25
Independent Claim
74 words
A method for forming an insulated gate field effect transistor comprising the steps of: forming a gate electrode on a substrate; forming an oxide film on a surface of said gate electrode by applying a voltage; forming a gate insulating film on said oxide film; forming a semiconductor film on said gate insulating film; forming source and drain regions in said semiconductor film, wherein said voltage is a D.C. voltage containing an A.C. component.
Claim 26
Independent Claim
74 words
A method for forming an insulated gate field effect transistor comprising the steps of: forming a gate electrode on a substrate; forming an oxide film on a surface of said gate electrode by applying a voltage; forming a gate insulating film on said oxide film; forming a semiconductor film on said gate insulating film; forming source and drain regions in said semiconductor film, wherein said voltage is a D.C. voltage containing an A.C. component.
Claim 27
Dependent Claim
18 words
A method according to claim 19 wherein said A.C. component has a frequency of 1 to 10 Hz.
Claim 28
Independent Claim
83 words
A method for forming an insulated gate field effect transistor comprising the steps of: forming a gate electrode on a substrate; forming an oxide film on a surface of said gate electrode by applying a voltage; forming a gate insulating film on said oxide film; forming a semiconductor film on said gate insulating film, said semiconductor film having a channel region therein; and forming source and drain regions in said semiconductor film, wherein said voltage is a D.C. voltage containing an A.C. component.
Claim 29
Independent Claim
83 words
A method for forming an insulated gate field effect transistor comprising the steps of: forming a gate electrode on a substrate; forming an oxide film on a surface of said gate electrode by applying a voltage; forming a gate insulating film on said oxide film; forming a semiconductor film on said gate insulating film, said semiconductor film having a channel region therein; and forming source and drain regions in said semiconductor film, wherein said voltage is a D.C. voltage containing an A.C. component.
Claim 30
Dependent Claim
18 words
A method according to claim 21 wherein said A.C. component has a frequency of 1 to 10 Hz.
Claim 31
Independent Claim
68 words
A method for forming an insulated gate field effect transistor comprising the steps of: forming source and drain regions on a substrate; forming a semiconductor film on said source/drain regions and said substrate; forming a gate electrode on said gate insulating film; forming an oxide film on a surface of said gate electrode by applying a voltage, wherein said voltage is a D.C. voltage containing an A.C. component.
Claim 32
Independent Claim
68 words
A method for forming an insulated gate field effect transistor comprising the steps of: forming source and drain regions on a substrate; forming a semiconductor film on said source/drain regions and said substrate; forming a gate electrode on said gate insulating film; forming an oxide film on a surface of said gate electrode by applying a voltage, wherein said voltage is a D.C. voltage containing an A.C. component.
Claim 33
Dependent Claim
18 words
A method according to claim 23 wherein said A.C. component has a frequency of 1 to 10 Hz.
References Cited (Backward Citations)
US3669856A
Cited
US3862017A
Cited
US3935084A
Cited
US4147598A
Cited
US4176342A
Cited
US4310586A
Cited
US4338176A
Cited
US4519676A
Cited
US4566952A
Cited
US5064512A
Cited
US4931151A
Cited
US5132003A
Cited
US5132200A
Cited
US5289030A
Cited
US5202274A
Cited
US5545571A
Cited
US5308998A
Cited
US5650338A
Cited
US5437952A
Cited
JPH06275646A
Cited
JPH06275647A
Cited
US5747355A
Cited
JPH06326309A
Cited
JPH06331582A
Cited
US5620905A
Cited
US5576231A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 2002-05-03 | 2002-11-02 | 2003-05-04 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 2006-05-03 | 2006-11-02 | 2007-05-04 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2010-05-03 | 2010-11-02 | 2011-05-04 | $7700.00 | Window Closed / Lapsed |