US4895779A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Method of forming a T shaped control electrode through an X-ray mask
Assignee: Mitsubishi Electric Corp
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Filing: 1988-08-11
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Granted: 1990-01-23
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Expires: 2008-08-11
Abstract
Abstract A positive resist film is formed on the major surface of a semiconductor substrate, to be irradiated with X-rays through an X-ray mask. The X-ray mask is formed by a joined member of an X-ray transmittable substrate and an X-ray absorber, and the X-ray absorber has an opening section of a T shape, in order to change the amount of transmission of the X-rays in desired positions. After the irradiation with the X-rays, the positive resist film is developed to obtain a resist film having an opening section of a desired T shape. A film for providing a control electrode is formed in the opening section of the resist film and the resist film is removed, thereby to form a T-shaped control electrode on the semiconductor substrate.
Inventors
- 👤 Nobuyuki Yoshioka
- 👤 Noriaki Ishio
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-31 07:43
CPC Classifications
G; G03; G03F; G03F1/00; G03F1/22; G03F7/00; G03F7/20; G03F7/2037; G03F7/2039; H; H10; H10D; H10D30/00; H10D30/01; H10D30/061; H10D30/0612; H10D30/0614; H10D64/00; H10D64/01; H10D64/012; H10D64/0124; H10D64/0125; Y; Y10; Y10S; Y10S430/00; Y10S430/167; Y10S430/168; Y10S438/00; Y10S438/942; Y10S438/948; Y10S438/949
Claims Analysis
Total Claims: 13
Claim 1
Independent Claim
158 words
A method of manufacturing an X-ray mask for forming a T-shaped control electrode having a section of a T shape, said method further comprising: a step of preparing a substrate for transmitting X-rays; a step of forming a first absorber not transmitting X-rays on said substrate; a step of forming a first resin film corresponding to the width of a lower portion of said T shape on said first absorber; a step of forming a second absorber not transmitting X-rays on said first absorber by utilizing said first resin film as a model; a step of forming a second resin film corresponding to the width of an upper portion of said T shape on parts of said first resin film and said second absorber; a step of forming a third absorber not transmitting X-rays on said second absorber by utilizing said second resin film as a model; and a step of removing said first and second resin films.
Claim 2
Independent Claim
158 words
A method of manufacturing an X-ray mask for forming a T-shaped control electrode having a section of a T shape, said method further comprising: a step of preparing a substrate for transmitting X-rays; a step of forming a first absorber not transmitting X-rays on said substrate; a step of forming a first resin film corresponding to the width of a lower portion of said T shape on said first absorber; a step of forming a second absorber not transmitting X-rays on said first absorber by utilizing said first resin film as a model; a step of forming a second resin film corresponding to the width of an upper portion of said T shape on parts of said first resin film and said second absorber; a step of forming a third absorber not transmitting X-rays on said second absorber by utilizing said second resin film as a model; and a step of removing said first and second resin films.
Claim 3
Dependent Claim
39 words
A method of manufacturing an X-ray mask for forming a T-shape control electrode in accordance with claim 1, comprising the additional step of: removing said first absorber that becomes exposed by removal of said first and second resin films.
Claim 4
Independent Claim
425 words
A method of manufacturing an X-ray mask for forming a T-shape control electrode having a section of a T shape, said method comprising: a step of preparing a substrate for transmitting X-rays; a step of forming a first absorber not transmitting X-rays on said substrate; a step of forming a first resin film on said first absorber; a step of forming a first metal film on said first resin film; a step of forming a first electron beam resist film on said first metal film; a step of exposing said first electron beam resist film by an electron beam exposurre technique to form a first resist pattern corresponding to a lower width of said T shape; a step of removing a portion of said first metal film by utilizing said first resist pattern as a mask and leaving corresponding residual portions of said first metal film; a step of removing said first resist pattern and a portion of said first resin film by utilizing said residual portions of said first metal film as a mask; a step of removing said residual portions of first metal film and exposing corresponding portions of said first resin film; a step of forming a second absorber not transmitting X-rays on said first absorber by utilizing residual portions of said first resin film as a model; a step of forming a second resin film on said second absorber including said residual portions of said first resin film; a step of forming a second metal film on said second resin film; a step of forming a second electron beam resist film on said second metal film; a step of exposing said second electron beam resist film by an electron beam exposure technique to form a second resist pattern corresponding to the width of an upper portion of said T shape; a step of removing a portion of said second metal film by utilizing said second resist pattern as a mask and leaving corresponding residual portions of said second metal film; a step of removing said second resist pattern and a portion of said second resin film by utilizing said residual portions of said second metal film as a mask; a step of removing said residual portions of second metal film and exposing corresponding portions of said second resin film; a step of forming a third absorber not transmitting X-rays on said second absorber by utilizing said residual portions of said second resin film as a model; and a step of removing said residual portions of said first and second resin films.
Claim 5
Independent Claim
425 words
A method of manufacturing an X-ray mask for forming a T-shape control electrode having a section of a T shape, said method comprising: a step of preparing a substrate for transmitting X-rays; a step of forming a first absorber not transmitting X-rays on said substrate; a step of forming a first resin film on said first absorber; a step of forming a first metal film on said first resin film; a step of forming a first electron beam resist film on said first metal film; a step of exposing said first electron beam resist film by an electron beam exposurre technique to form a first resist pattern corresponding to a lower width of said T shape; a step of removing a portion of said first metal film by utilizing said first resist pattern as a mask and leaving corresponding residual portions of said first metal film; a step of removing said first resist pattern and a portion of said first resin film by utilizing said residual portions of said first metal film as a mask; a step of removing said residual portions of first metal film and exposing corresponding portions of said first resin film; a step of forming a second absorber not transmitting X-rays on said first absorber by utilizing residual portions of said first resin film as a model; a step of forming a second resin film on said second absorber including said residual portions of said first resin film; a step of forming a second metal film on said second resin film; a step of forming a second electron beam resist film on said second metal film; a step of exposing said second electron beam resist film by an electron beam exposure technique to form a second resist pattern corresponding to the width of an upper portion of said T shape; a step of removing a portion of said second metal film by utilizing said second resist pattern as a mask and leaving corresponding residual portions of said second metal film; a step of removing said second resist pattern and a portion of said second resin film by utilizing said residual portions of said second metal film as a mask; a step of removing said residual portions of second metal film and exposing corresponding portions of said second resin film; a step of forming a third absorber not transmitting X-rays on said second absorber by utilizing said residual portions of said second resin film as a model; and a step of removing said residual portions of said first and second resin films.
Claim 6
Dependent Claim
45 words
A method of manufacturing an X-ray mask for forming a T-shaped control electrode in accordance with claim 3, said method further comprising: a step of removing said first absorber that is exposed by removal of said residual portions of said first and second resin films.
Claim 7
Dependent Claim
30 words
A method of manufacturing an X-ray mask for forming a T-shaped control electrode in accordance with claim 4, wherein: said first, second and third absorbers comprise of the same material.
Claim 8
Dependent Claim
39 words
A method of manufacturing an X-ray mask for forming a T-shaped control electrode in accordance with claim 4, wherein: said first and second resin films and said first and second metal films are removed by reactive ion etching (RIE).
Claim 9
Dependent Claim
29 words
A method of manufacturing an X-ray mask for forming a T-shaped control electrode in accordance with claim 5, wherein: said first and second absorbers are formed by electrolytic plating.
Claim 10
Dependent Claim
25 words
A method of manufacturing an X-ray mask for forming, a T-shaped control electrode in accordance with claim 3, wherein: said substrate comprises silicon nitride (SiN).
Claim 11
Dependent Claim
29 words
A method of manufacturing an X-ray mask for forming a T-shaped control electrode in accordance with claim 5, wherein: said first, second and third absorbers are of gold (Au).
Claim 12
Dependent Claim
28 words
A method of manufacturing an X-ray mask for forming a T-shaped control electrode in accordance with claim 5, wherein: said first, second and third absorbers comprise tantalum (Ta).
Claim 13
Dependent Claim
27 words
A method of manufacturing an X-ray mask for forming a T-shaped control electrode in accordance with claim 3, wherein: said first and second resin films comprise polyimide.
References Cited (Backward Citations)
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| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
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| 3.5 Years (Year 4) | 1993-01-22 | 1993-07-24 | 1994-01-23 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1997-01-22 | 1997-07-24 | 1998-01-23 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2001-01-22 | 2001-07-24 | 2002-01-23 | $7700.00 | Window Closed / Lapsed |