Polymeric materials and methods for making the polymeric materials
View Patent ↗Polymeric materials, methods for making the polymeric materials, and photoresist formulations utilizing the polymeric materials are disclosed. In one aspect, a polymeric material is provided including a condensation product of a reaction mixture comprising an aldehyde with a phenolic monomer composition comprising m-cresol, p-cresol, 3,5-dimethyl phenol, and 2,5-dimethyl phenol. The polymeric material may be further contacted with a photoactive compound and a solvent to form a photoresist formulation.
1. A method for forming a polymeric material, comprising:
charging m-cresol, p-cresol, 3,5-dimethyl phenol, 2,5-dimethyl phenol, and an acid catalyst to a reactor to form a reaction mixture;
heating the reaction mixture to a temperature from about 70° C. to about 110° C.;
charging an aldehyde to the reaction mixture; and
condensing the reaction mixture, wherein the condensing the reaction mixture comprises:
refluxing the reaction mixture for a first period of time;
distilling the reaction mixture for a second period of time; and
removing residual water and free monomers; and
adding p-cresol after the refluxing the reaction mixture and prior to the distilling the reaction mixture.
2. The method of claim 1 , wherein the charging m-cresol, p-cresol, 3,5-dimethyl phenol, 2,5-dimethyl phenol, and an acid catalyst comprises charging:
about 50% to about 70% by weight of m-cresol;
about 20% to about 30% by weight of p-cresol;
about 5% to about 20% by weight of 3,5-dimethyl phenol;
about 5% to about 15% by weight of 2,5-dimethyl phenol; and
about 1% to about 2% by weight of the acid catalyst.
3. The method of claim 1 , wherein the charging the aldehyde to the reaction mixture comprises charging aldehyde at a molar ratio of aldehyde to total moles of phenolic monomers of less than 1:1.
4. The method of claim 1 , further comprising contacting the polymeric material with a photoactive compound and a solvent.
5. The method of claim 1 , wherein the polymeric material has a glass transition temperature from about 110° C. to about 135° C.
6. The method of claim 1 , wherein the aldehyde is a carbonyl compound represented by the formula (I):
R 1 —C(O)—R 2 , (I)
wherein R 1 and R 2 are each selected from the group consisting of a hydrogen atom, an alkyl group, an alkenyl group, and aralkyl group, and aryl group, and combinations thereof.
7. The method of claim 6 , wherein the aldehyde is selected from the group consisting of formaldehyde, paraformaldehyde, benzaldehyde, furfural, acetaldehyde, and combinations thereof.
8. The method of claim 1 , wherein the polymeric material has a viscosity from about 30 centistokes to about 95 centistokes.
9. The method of claim 1 , wherein the acid catalyst is selected from the group consisting of an inorganic acid, an organic acid, an anhydride, an ion-exchange resin, and combinations thereof.
10. The method of claim 9 , wherein the acid catalyst is selected from the group consisting of oxalic acid, formic acid, acetic acid, hydrochloric acid, nitric acid, sulphuric acid, citric acid, maleic anhydride, succinic anhydride, styrene divinylbenzene co-polymer with sulfonic acid groups, polyacrylic carboxylic acid, and combinations thereof.
11. The method of claim 4 , wherein the photoactive compound comprises a 1,2-quinonediazide compound, a quinonediazidosulfonic acid ester compound, a naphthoquinonediazide, and combinations thereof.
12. The method of claim 4 , wherein the solvent comprises an organic solvent selected from the group of alcohols, ethers, esters, ketones, alkyl ether acetates, acid esters, aromatic hydrocarbons, fatty acids, amides, and combinations thereof.
13. The method of claim 1 , wherein the polymeric material has an alkaline dissolution rate from about 20 to about 600 Å/Sec.