US3930857A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Resist process
Assignee: International Business Machines Corp
•
Filing: 1973-05-03
•
Granted: 1976-01-06
•
Expires: 1993-05-03
Abstract
Abstract A resist mask, whose configuration is changed during processing, is formed by varying the exposure energy across a resist layer and then conducting successive development steps using developers having increasing solvent power to remove progressively more of the resist layer with each step.
Inventors
- 👤 Diana Jean Bendz
- 👤 Gerald Andrei Bendz
- 👤 Anne Marie Wildman
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-29 02:36
CPC Classifications
G; G03; G03F; G03F1/00; G03F1/54; G03F1/50; G03F7/00; G03F7/004; G03F7/022; G03F7/20; Y; Y10; Y10S; Y10S438/00; Y10S438/942; Y10S438/948; Y10S438/98
Claims Analysis
Total Claims: 8
Claim 1
Independent Claim
180 words
A resist process comprising: a. forming a resist layer on a substrate, b. exposing said layer patternwise while varying the exposure energy across the pattern to form a plurality of exposed regions in said layer having differing solubility rates, c. developing said resist layer with a first developer so as to remove the portions of said layer having the greatest solubility rate from said substrate and form a resist mask having a first configuration, d. subjecting the exposed portions of said substrate to a first additive or subtractive treatment with the remainder of said resist layer acting to protect the covered portions of said substrate from the treatment, e. developing the resist layer with a second, more concentrated, developer so as to remove the patterns of said layer having the next greatest solubility rate from said substrate to form a resist mask having a second configuration, f. subjecting the exposed portions of said substrate to a second additive or subtractive treatment with the remainder of said resist layer acting to protect the covered portions of said substrate from said treatment.
Claim 2
Dependent Claim
180 words
A resist process comprising: a. forming a resist layer on a substrate, b. exposing said layer patternwise while varying the exposure energy across the pattern to form a plurality of exposed regions in said layer having differing solubility rates, c. developing said resist layer with a first developer so as to remove the portions of said layer having the greatest solubility rate from said substrate and form a resist mask having a first configuration, d. subjecting the exposed portions of said substrate to a first additive or subtractive treatment with the remainder of said resist layer acting to protect the covered portions of said substrate from the treatment, e. developing the resist layer with a second, more concentrated, developer so as to remove the patterns of said layer having the next greatest solubility rate from said substrate to form a resist mask having a second configuration, f. subjecting the exposed portions of said substrate to a second additive or subtractive treatment with the remainder of said resist layer acting to protect the covered portions of said substrate from said treatment.
Claim 3
Dependent Claim
31 words
The process of claim 1 wherein the exposure step comprises the step of exposing said layer through a graded mask having areas of differing optical density to the transmittal of light.
Claim 4
Dependent Claim
20 words
The process of claim 1 wherein said substrate is a dielectric material which is coated with an electrically conductive layer.
Claim 5
Dependent Claim
22 words
The process of claim 3 wherein said first and second treatments are etching steps to remove portions of said electrically conductive layer.
Claim 6
Dependent Claim
21 words
The process of claim 3 wherein said first treatment is an etching step and said second treatment is a plating step.
Claim 7
Dependent Claim
12 words
The process of claim 1 wherein said substrate is a semiconductor device.
Claim 8
Dependent Claim
71 words
The process of claim 2 wherein the resist is an alkali soluble positive acting resist containing a meta-cresol formaldehyde novolak resin having an average molecular weight of about 1,000, and a sensitizer which is the 2-diazo-1-oxo-naphthalene-5-sulfonic acid ester of 2,3,4-trihydroxybenzophenone and said developers are aqueous alkaline solutions with said first developer being more dilute in that it contains a lower solids content by weight of alkaline material than said second developer.
References Cited (Backward Citations)
US3152938A
Cited
US3458311A
Cited
US3600243A
Cited
US3535137A
Cited
US3730717A
Cited
US3649393A
Cited
US3756827A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1979-01-05 | 1979-07-07 | 1980-01-06 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1983-01-05 | 1983-07-07 | 1984-01-06 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1987-01-05 | 1987-07-07 | 1988-01-06 | $7700.00 | Window Closed / Lapsed |