Method for forming pattern using anti-reflective coating composition comprising photoacid generator
The present invention relates to a method for forming a pattern by negative tone development (NTD) which is prepared by forming an anti-reflective coating composition layer comprising a photoacid generator between the substrate and the photoresist composition layer, and thus exhibits improved line width (CD) in the pattern and prevents pattern collapse owing to thorough activation of de-blocking of the photoresist composition layer during the exposure process.
1. A method for forming a pattern by negative tone development, comprising the steps of:
(1) forming on a substrate a layer of an anti-reflective coating composition consisting of (a) an organic polymer, (b) an onium-salt based photoacid generator, and (c) a crosslinker, wherein the organic polymer comprises: (a-1) at least one unit derived from a cyanurate-based compound having two or more groups selected from carboxy and carboxyester; and (a-2) at least one unit derived from a diol or a polyol;
(2) forming a layer of a photoresist composition on the anti-reflective coating composition layer;
(3) exposing the photoresist composition layer and the anti-reflective coating composition layer to activating radiation at the same time, followed by baking; and
(4) developing the exposed photoresist composition layer with an organic solvent developer.
2. The method of claim 1 , wherein the onium salt is a salt of a sulfonium having an aromatic group and a sulfonate.
3. The method of claim 1 , wherein the anti-reflective coating composition comprises from 0.01 to 15 wt % of the photoacid generator based on the total weight of solid content in the composition.
4. The method of claim 1 , wherein the crosslinker is a glycoluril-based crosslinker.
5. The method of claim 1 , wherein the photoresist composition comprises a matrix polymer, a photoacid generator and a solvent, wherein the matrix polymer comprises at least one unit having an acid-cleavable protecting group.
6. The method of claim 1 , wherein prior to forming the anti-reflective coating composition layer, a second anti-reflective coating composition layer that is different than the anti-reflective coating composition layer is formed on the substrate, and the anti-reflective coating composition layer is formed on the second anti-reflective coating composition layer.
7. The method of claim 1 wherein (a-1) may be at least one compound derived from a compound represented by the following Formula 1:
wherein at least two of R 1 OOC(CX 2 ) n —, R 2 —, and R 3 OOC(CX 2 ) m — represent different acids, or ester groups;
R 1 , R 2 , R 3 and X each independently represent hydrogen or a non-hydrogen substituent; and n and m are the same as or different from each other, and each is an integer greater than 0.
8. The method of claim 7 wherein R 1 , R 2 , R 3 and X each independently represent hydrogen a substituted or unsubstituted C 1-10 alkyl group, a substituted or unsubstituted C 2-10 alkenyl or C 2-10 alkynyl group, a substituted or unsubstituted C 1-10 alkanoyl group, a substituted or unsubstituted C 1-10 alkoxy group, an epoxy group, a substituted or unsubstituted C 1-10 alkylthio group, a substituted or unsubstituted C 1-10 alkylsulfinyl group, a substituted or unsubstituted C 1-10 alkylsulfonyl group, a substituted or unsubstituted carboxyl group, a substituted or unsubstituted —COO—C 1-8 alkyl group, a substituted or unsubstituted C 6-12 aryl group, or a substituted or unsubstituted 5- to 10-membered heteroalicyclic or heteroaryl group; and
n and m are the same as or different from each other, and each is an integer greater than 0.
9. The method of claim 1 wherein the anti-reflective coating composition is cured prior to forming the photoresist layer on the anti-reflective coating composition.
10. The method of claim 9 wherein the cured antireflective coating composition is substantially insoluble to an alkaline aqueous developer.
11. A method for forming a pattern by negative tone development, comprising the steps of:
(1) forming on a substrate a layer of an anti-reflective coating composition consisting of:
(a) an organic polymer comprising: (a-1) at least one unit derived from a cyanurate-based compound having two or more groups selected from carboxy and carboxyester; and (a-2) at least one unit derived from a diol or a polyol;
(b) a photoacid generator that is a sulfonium salt comprising an aromatic group and a sulfonate anion in an amount of 0.01 to 15 wt % of the photoacid generator based on the total weight of solid content in the composition, and
(c) a glycoluril-based crosslinker;
(2) forming a layer of a photoresist composition on the anti-reflective coating composition layer;
(3) exposing the photoresist composition layer and the anti-reflective coating composition layer to activating radiation at the same time, followed by baking; and
(4) developing the exposed photoresist composition layer with an organic solvent developer.