Claims
- 1. The process for forming positive resist patterns on a substrate comprising:
- (1) coating said substrate with a radiation-sensitive composition useful as a positive-working photoresist, said composition comprising an admixture of o-quinonediazide compound and a novolak resin composition consisting of the reaction product of a para-, para-bonded bisphenol having formula (A): ##STR7## wherein R.sub.1 =lower alkyl group having 1-4 carbon atoms, halogen, or lower alkoxy group having 1-4 carbon atoms; wherein
- R.sub.2 =hydrogen or lower alkyl group having 1-4 carbon atoms; and wherein
- X is selected from the group consisting of CH.sub.2, CH(CH.sub.3), C(CH.sub.3).sub.2, O, and S;
- with a bismethylol monomer selected from a difunctional ortho-, ortho-phenolic bismethylol of formula (B), a difunctional ortho-, para-phenolic bismethylol of formula (C), or mixtures thereof: ##STR8## wherein R.sub.3 is selected from CH.sub.3, CH.sub.2 CH.sub.3, Cl, and Br; wherein
- R.sub.4 is selected from H and CH.sub.3 ; and wherein the amount of said o-quinonediazide compound being about 5% to about 40% by weight and the amount of said binder resin being about 50% to 95% by weight, based on the total solid content of said radiation-sensitive composition;
- (2) subjecting said coating on said substrate to an image-wise exposure of radiation energy; and
- (3) subjecting said image-wise exposed coated substrate to a developing solution wherein the exposed areas of said radiation-exposed coating are dissolved and removed from the substrate, thereby resulting in positive image-wise pattern in the coating.
- 2. The process of claim 1 wherein the mole ratio of the monomers of formula (A) to the combined monomers of formulae (B) and (C) is from about 1:0.8 to about 1:1.2.
- 3. The process of claim 1 wherein R.sub.1 =CH.sub.3, Cl, Br, or OCH.sub.3 ; R.sub.2 =H or CH.sub.3 ; and X=CH.sub.2, CH(CH.sub.3), or C(CH.sub.3).sub.2 in formula (A).
- 4. The process of claim 1 wherein R.sub.3 =CH.sub.3 or C(CH.sub.2).sub.3 ; and R.sub.4 =H in both formulae (B) and (C).
- 5. The process of claim 1 wherein said para-, para-bonded bisphenol is 2,2"-bis(4-hydroxy-3-methylphenyl) propane; wherein said difunctional ortho-, ortho phenolic bismethylol is p-cresol bismethylol; and wherein said para, ortho-phenolic bismethylol is o-cresol bismethylol.
- 6. The process of claim 1 wherein said developing solution comprises an aqueous solution of an alkali metal hydroxide or silicates or an aqueous solution of tetramethylammonium hydroxide.
Parent Case Info
This application is a division of application Ser. No. 07/787,454 filed Nov. 4, 1991, now U.S. Pat. No. 5,306,594, which is incorporated herein by reference in its entirety.
US Referenced Citations (1)
Number |
Name |
Date |
Kind |
5128230 |
Templeton et al. |
Jul 1992 |
|
Non-Patent Literature Citations (1)
Entry |
Honda et al. "Studies of Dissolution Inhibition Mechanism of DNQ-Novolak Resist [II] Effect of Extended Ortho-Ortho Bond in Novalak", SPIE vol. 1466 Advances in Resist Technology & Processing VIII (1991) pp. 141 et seq. |
Divisions (1)
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Number |
Date |
Country |
Parent |
787454 |
Nov 1991 |
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