US5300403A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Line width control in a radiation sensitive polyimide
Assignee: International Business Machines Corp
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Filing: 1992-06-18
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Granted: 1994-04-05
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Expires: 2012-06-18
Abstract
Abstract Standard processing techniques for creating a patterned polyimide film from a radiation sensitive polyimide film forming composition are modified to include a post-develop, flood exposure/hardening step which crosslinks precursors of the polyimide film prior to curing. The flood exposure/hardening step prevents pull-back of the wall profile which occurs during the shrinkage of radiation sensitive polyimide film forming composition which occurs during thermal curing.
Inventors
- 👤 Marie Angelopolus
- 👤 Daniel G. Berger
- 👤 Eric D. Perfecto
- 👤 Peter J. Wilkens
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-01 13:58
CPC Classifications
G; G03; G03F; G03F7/00; G03F7/26; G03F7/40
Claims Analysis
Total Claims: 17
Claim 1
Independent Claim
285 words
A method of retaining the definition of features in a radiation sensitive polyimide film forming composition subsequent to imidization cure, comprising the steps of: applying a radiation sensitive polyimide film forming composition to a substrate; patterning said radiation sensitive polyimide film forming composition by imaging and developing to produce a stencil pattern of said radiation sensitive polyimide film forming composition, said stencil pattern having a bottom surface adjacent said substrate and a top surface spaced from said substrate by a first thickness of said radiation sensitive polyimide film forming composition, said stencil pattern having features formed therein by said imaging and developing of said patterning step wherein portions of said stencil pattern cover portions of said substrate and wherein portions of said substrate are not covered by said stencil pattern, said features being defined by sidewalls of said radiation sensitive polyimide film forming composition which extend between said bottom surface and said top surface of said radiation sensitive polyimide film forming composition; post development exposing said stencil pattern to radiation at an energy level and for a time sufficient to crosslink and harden said radiation sensitive polyimide film forming composition at said sidewalls of said features of said stencil pattern to a point which will reduce the tendency of said sidewalls of said features in said radiation sensitive polyimide film forming composition to retract at said top surface during thermal curing; and thermally curing said radiation sensitive polyimide film forming composition in said stencil pattern to create a patterned polyimide film having a bottom surface adjacent said substrate and a top surface spaced from said substrate by a second thickness which is smaller than said first thickness of said radiation sensitive polyimide film forming composition.
Claim 2
Independent Claim
285 words
A method of retaining the definition of features in a radiation sensitive polyimide film forming composition subsequent to imidization cure, comprising the steps of: applying a radiation sensitive polyimide film forming composition to a substrate; patterning said radiation sensitive polyimide film forming composition by imaging and developing to produce a stencil pattern of said radiation sensitive polyimide film forming composition, said stencil pattern having a bottom surface adjacent said substrate and a top surface spaced from said substrate by a first thickness of said radiation sensitive polyimide film forming composition, said stencil pattern having features formed therein by said imaging and developing of said patterning step wherein portions of said stencil pattern cover portions of said substrate and wherein portions of said substrate are not covered by said stencil pattern, said features being defined by sidewalls of said radiation sensitive polyimide film forming composition which extend between said bottom surface and said top surface of said radiation sensitive polyimide film forming composition; post development exposing said stencil pattern to radiation at an energy level and for a time sufficient to crosslink and harden said radiation sensitive polyimide film forming composition at said sidewalls of said features of said stencil pattern to a point which will reduce the tendency of said sidewalls of said features in said radiation sensitive polyimide film forming composition to retract at said top surface during thermal curing; and thermally curing said radiation sensitive polyimide film forming composition in said stencil pattern to create a patterned polyimide film having a bottom surface adjacent said substrate and a top surface spaced from said substrate by a second thickness which is smaller than said first thickness of said radiation sensitive polyimide film forming composition.
Claim 3
Dependent Claim
27 words
A method as recited in claim 1 wherein said step of post development exposing is performed with radiation of all wavelengths in the ultraviolet and visible spectrum.
Claim 4
Dependent Claim
26 words
A method as recited in claim 1 wherein said step of post development exposing is performed with radiation at wavelengths ranging from 300 to 500 nanometers.
Claim 5
Dependent Claim
23 words
A method as recited in claim 1 further comprising the step of heating aid stencil pattern during said step of post development exposing.
Claim 6
Dependent Claim
23 words
A method as recited in claim 4 wherein said step of heating is performed for said time of said post development exposing step.
Claim 7
Dependent Claim
25 words
A method as recited in claim 4 wherein said step of heating is performed for part of said time of said post development exposing step.
Claim 8
Dependent Claim
30 words
A method as recited in claim 4 wherein said step of heating is performed at a temperature in excess of 100° C. but less than that required for thermal curing.
Claim 9
Dependent Claim
20 words
A method as recited in claim 7 wherein said step of heating is performed at a temperature below 100° C.
Claim 10
Dependent Claim
24 words
A method as recited in claim 1 wherein said step of post development exposing is performed for a time period up to one hour.
Claim 11
Dependent Claim
32 words
A method as recited in claim 1 wherein said step of post development exposing is performed using radiation selected from the group consisting of UV/visible radiation, electron beam, ion beam, and x-rays.
Claim 12
Dependent Claim
27 words
A method as recited in claim 1 wherein said step of post development exposing provides an exposure dose of radiation ranging from 200 mJ to 10 J.
Claim 13
Dependent Claim
36 words
A method as recited in claim 1 wherein said step of thermally curing is performed at a temperature sufficient to imidize polyimide precursor compounds in said radiation sensitive polyimide film forming composition applied to said substrate.
Claim 14
Dependent Claim
25 words
A method as recited in claim 12 wherein said step of thermally curing is performed at a temperature on the order of approximately 400° C.
Claim 15
Dependent Claim
25 words
A method as recited in claim 1 wherein said radiation sensitive film forming composition applied during said applying step includes tetracarboxylic acid dianhydrides and diamines.
Claim 16
Dependent Claim
26 words
A method as recited in claim 1 further comprising the step of baking said radiation sensitive polyimide film forming composition prior to said step of patterning.
Claim 17
Dependent Claim
99 words
A method as recited in claim 1 wherein said patterning step produces a stencil pattern with both isolated and dense features wherein each of said isolated features are separated from other isolated or dense features in said stencil pattern by more than 100 microns and each of said dense features are separated from other isolated or dense features by less than 100 microns, and wherein said post development exposing step is sufficient to reduce differences in relative retraction of said sidewalls at said top surface of said radiation sensitive polyimide film forming composition between said isolated and dense features.
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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) | 1997-04-04 | 1997-10-04 | 1998-04-05 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 2001-04-04 | 2001-10-04 | 2002-04-05 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2005-04-04 | 2005-10-04 | 2006-04-05 | $7700.00 | Window Closed / Lapsed |