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US5429910A Expired / Lapsed US ⏱️ 0.0 years remaining

Method of forming a critical resist pattern

Assignee: Renesas Electronics Corp
•
Filing: 1993-05-12
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Granted: 1995-07-04
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Expires: 2013-05-12
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Abstract

Abstract A resist pattern having an accurate rectangular sectional configuration and high dimension controllability can be formed using a conventional chemical amplification positive type resist. A chemical amplification positive type resist layer 3 including a base resin, and a protonic acid generating agent decomposed by photochemical reaction to generate protonic acid and a dissolution inhibitor is formed on a semiconductor substrate 2. Light 8 is selectively directed to the chemical amplification positive type resist layer 3 to form an image. The chemical amplification positive type resist layer 3 after irradiation of light 8 has its surface treated with an acid solution 1 so that the surface of the resist layer 3 includes acid. The chemical amplification positive type resist layer 3 treated with acid is baked and then developed to form a resist pattern 7.

Inventors

  • 👤 Tetsuro Hanawa

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-10-30 20:31
CPC Classifications
G; G03; G03F; G03F7/00; G03F7/26; G03F7/38; G03F7/004; G03F7/0045; Y; Y10; Y10S; Y10S430/00; Y10S430/162

Claims Analysis

Total Claims: 19
Claim 1
Independent Claim 152 words
A method of forming a critical resist pattern, comprising the steps of: forming a chemical amplification positive type resist layer including a base resin and a protonic acid generating agent decomposed by photochemical reaction to generate protonic acid on a semiconductor substrate, selectively directing light to said chemical amplification positive type resist layer to form an image and to form protonic acid in exposed areas of the chemical amplification positive type resist layer, treating the surface of said chemical amplification positive type resist layer with acid after irradiation of said light so that the surface of said resist layer includes acid, the acid being selected from the group consisting of sulfuric acid solution, nitric acid solution, organic sulfonic acid solution, organic carboxylic acid solution and acetic acid solution, baking said acid treated chemical amplification positive type resist layer, and developing said chemical amplification positive type resist layer to form a resist pattern.
Claim 2
Independent Claim 152 words
A method of forming a critical resist pattern, comprising the steps of: forming a chemical amplification positive type resist layer including a base resin and a protonic acid generating agent decomposed by photochemical reaction to generate protonic acid on a semiconductor substrate, selectively directing light to said chemical amplification positive type resist layer to form an image and to form protonic acid in exposed areas of the chemical amplification positive type resist layer, treating the surface of said chemical amplification positive type resist layer with acid after irradiation of said light so that the surface of said resist layer includes acid, the acid being selected from the group consisting of sulfuric acid solution, nitric acid solution, organic sulfonic acid solution, organic carboxylic acid solution and acetic acid solution, baking said acid treated chemical amplification positive type resist layer, and developing said chemical amplification positive type resist layer to form a resist pattern.
Claim 3
Dependent Claim 23 words
The method according to claim 1, wherein said acid treatment is carried out by dipping said semiconductor substrate in a solution of acid.
Claim 4
Dependent Claim 22 words
The method according to claim 1, wherein the acid treatment is carried out by applying solution of acid on said semiconductor substrate.
Claim 5
Dependent Claim 31 words
The method according to claim 3, wherein the acid treatment is carried out by applying on said semiconductor substrate acid heated at a temperature from room temperature up to 80° C.
Claim 6
Dependent Claim 31 words
The method according to claim 1, wherein the acid treatment is carried out by bringing into contact the surface of said chemical amplification positive type resist layer with vapor of acid.
Claim 7
Dependent Claim 25 words
The method according to claim 1, wherein the acid treatment is carried out with heating at a temperature from room temperature up to 80° C.
Claim 8
Dependent Claim 13 words
The method according to claim 1, wherein said base resin comprises poly (p-t-butoxycarbonyl-oxystyrene).
Claim 9
Dependent Claim 17 words
The method according to claim 1, wherein said acid comprises sulfuric acid solution or nitric acid solution.
Claim 10
Dependent Claim 14 words
The method according to claim 8, wherein the concentration of said acid is 0.001N-1N.
Claim 11
Dependent Claim 19 words
The method according to claim 1, wherein said acid comprises organic sulfonic acid solution or organic carboxylic acid solution.
Claim 12
Dependent Claim 31 words
The method according to claim 10, wherein the concentration of said organic acid in solution is within a range of from 0.001N to a saturation concentration of the acid in solution.
Claim 13
Dependent Claim 13 words
The method according to claim 1, wherein said light comprises deep UV light.
Claim 14
Dependent Claim 15 words
The method according to claim 12, wherein said deep UV light comprises excimer laser light.
Claim 15
Dependent Claim 32 words
The method according to claim 1, wherein said protonic acid generating agent is selected from the group consisting of triphenyl sulfonium hexafluoro antimonate, triphenyl sulfonium hexafluoro arsenate, and triphenyl sulfonium trifluoro methanesulfonate.
Claim 16
Dependent Claim 19 words
The method according to claim 1, wherein said chemical amplification positive type resist layer further includes a dissolution inhibitor.
Claim 17
Dependent Claim 12 words
The method according to claim 1, wherein the acid comprises acetic acid.
Claim 18
Dependent Claim 22 words
The method according to claim 1, wherein the organic sulfonic acid solution comprises benzene sulfonic acid solution or p-toluene sulfonic acid solution.
Claim 19
Dependent Claim 20 words
The method according to claim 1, wherein the organic carboxylic acid solution comprises benzoic acid solution or phthalic acid solution.

References Cited (Backward Citations)

US4981770A Cited
US5258266A Cited
US5240812A Cited
US5326675A Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1998-07-03 1999-01-02 1999-07-04 $2000.00 Window Closed / Lapsed
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