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US4886734A
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Electron-beam positive polyimide
Assignee: International Business Machines Corp
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Filing: 1988-09-26
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Granted: 1989-12-12
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Expires: 2008-09-26
Abstract
Abstract An insoluble electron beam positive polyimide having the formula ##STR1## can be exposed by an electron beam to render the exposed areas soluble. The exposed areas can then be dissolved using a solvent to leave the pattern which can be used directly as an insulator layer in a semiconductor device.
Inventors
- 👤 James A. Moore
- 👤 Andrew N. Dasheff
- 👤 Frank B. Kaufman
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-06 12:55
CPC Classifications
G; G03; G03F; G03F7/00; G03F7/004; G03F7/039; C; C08; C08G; C08G73/00; C08G73/06; C08G73/10; C08G73/1046; C08G73/105; H; H01; H01B; H01B3/00; H01B3/18; H01B3/30; H01B3/303; H01B3/306; Y; Y10; Y10S; Y10S430/00; Y10S430/143
Claims Analysis
Total Claims: 7
Claim 1
Independent Claim
56 words
A method of forming a patterned layer comprising: forming a layer of insoluble polyimide having the formula: ##STR5## irradiating the layer with an electron beam to produce exposed and unexposed areas in the layer, the exposed areas becoming soluble; and dissolving the exposed areas from the layer using a solvent to form the patterned insoluble layer.
Claim 2
Independent Claim
56 words
A method of forming a patterned layer comprising: forming a layer of insoluble polyimide having the formula: ##STR5## irradiating the layer with an electron beam to produce exposed and unexposed areas in the layer, the exposed areas becoming soluble; and dissolving the exposed areas from the layer using a solvent to form the patterned insoluble layer.
Claim 3
Dependent Claim
14 words
A method according to claim 1 wherein the solvent is a polar, aprotic solvent.
Claim 4
Dependent Claim
24 words
A method according to claim 1 including irradiating the layer with an incident dosage of from about 200 to 500 micro-coulombs/cm 2 of energy.
Claim 5
Dependent Claim
42 words
A method according to claim 1 wherein the insoluble polyimide is formed by irradiating maleic anhydride to form cyclobutane tetracarboxylic dianhydride, reacting the cyclobutane tetracarboxylic dianhydride with oxydianiline to form polyamic acid and curing the polyamic acid to form the insoluble polyimide.
Claim 6
Dependent Claim
18 words
A method according to claim 4 including curing the polyamic acid into polyimide by heating the polyamic acid.
Claim 7
Dependent Claim
30 words
A method according to claim 5 including reacting the cyclobutane tetracarboxylic dianhydride with oxydianiline in the presence of a solvent chosen from a group consisting of dimethyl formamide and DMAC.
References Cited (Backward Citations)
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1992-12-11 | 1993-06-12 | 1993-12-12 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1996-12-11 | 1997-06-12 | 1997-12-12 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2000-12-11 | 2001-06-12 | 2001-12-12 | $7700.00 | Window Closed / Lapsed |