Antireflective coating composition and process thereof
View Patent ↗The invention related to an antireflective coating comprising a mixture of a first polymer and a second polymer, and a thermal acid generator, where the first polymer comprises at least one fluoroalcohol moiety, at least one aliphatic hydroxyl moiety, and at least one acid moiety other than fluoroalcohol with a pKa in the range of about 8 to about 11; where the second polymer is a reaction product of an aminoplast compound with a compound comprising at least one hydroxyl and/or at least one acid group. The invention further relates to a process for using the novel composition to form an image.
1. An antireflective coating comprising a mixture of a first polymer and a second polymer, and a thermal acid generator, where the first polymer comprises at least one fluoroalcohol moiety, at least one aliphatic hydroxyl moiety, and at least one acid moiety other than fluoroalcohol with a pKa in the range of about 8 to about 11; where the second polymer is a reaction product of an aminoplast compound with a compound comprising at least one hydroxyl and/or at least one acid group; wherein the first polymer further comprises a monomeric unit comprising an imide moiety derived from structure (8) or (9)
where R 1 , R 2 and R 3 are independently selected from hydrogen and (C 1 -C 4 )alkyl, R″ 4 is a linear (C 1 -C 10 )alkyl group or an (C 6 -C 14 )aryl moiety and R 8 is a direct valence bond or is a (C 1 -C 10 )alkylene spacer group.
2. The antireflective coating composition of claim 1 , where the first polymer further comprises an aromatic group.
3. The antireflective coating composition of claim 2 , where the aromatic group is a unit of structure
where Ar is an aryl moiety, where R 1 , R 2 and R 3 are independently selected from hydrogen and (C 1 -C 4 )alkyl, R 4 is a (C 1 -C 10 )alkyl group or an (C 6 -C 14 )aryl moiety R 5 is a direct valence bond or a spacer group R 6 and R 7 are independently selected from hydrogen, (C 1 -C 10 )alkyl group, an aryl moiety (C 6 -C 14 ), a (C 2 -C 8 )carbonyloxyalkyl, and (C 2 -C 8 )carbonyl.
4. The antireflective coating composition of claim 1 where the first polymer has structure (I)
(—P 1 —) u (—P 2 —) v (—P 3 —) w (—P 4 —) x (—P 5 —) y (I)
where P 1 is a monomeric unit comprising a fluoroalcohol moiety, P 2 is a monomeric unit comprising an aliphatic alcohol group; P 3 is a monomeric unit comprising an imide moiety of structure 8 or 9; P 4 is a monomeric unit comprising a base ionizable arylhydroxy moiety; P 5 is an optional monomeric repeat unit comprising an aryl chromophore moiety; u, v, w, x, y are representative of mole % proportion of repeat units in a polymer chain and where u, v, w and x are greater than 0 and y is zero or greater.
5. The antireflective coating composition of claim 1 , where the first polymer comprising fluoroalcohol group is a unit of structure (2)
where X is ethylenic unit or substituted ethylenic unit, W is selected from an alkylene and arylene group, and Rf 1 and Rf 2 are independently a fluoro(C 1 -C 4 )alkyl group.
6. The antireflective coating composition of claim 1 , where first polymer comprising the aliphatic hydroxyl moiety is a unit of structure (7)
where R 1 , R 2 and R 3 are independently selected from hydrogen and (C 1 -C 4 )alkyl, independently selected from hydrogen and (C 1 -C 4 )alkyl, R 4 is hydrogen or an (C 1 -C 10 )alkyl group, and R 9 is selected from a direct bond and a (C 1 -C 12 )alkyl spacer group.
7. The antireflective coating composition of claim 1 , where the first polymer comprises an acid moiety other than fluoroalcohol with a pKa in the range of about 8 to about 11 of structure (10a) or (10b),
where Ar is an aryl moiety, where R 1 , R 2 and R 3 are independently selected from hydrogen and (C 1 -C 4 )alkyl, R 4 is a (C 1 -C 10 )alkyl group or an (C 6 -C 14 )aryl moiety R 5 is a direct valence bond or a spacer group R 6 and R 7 are independently selected from hydrogen, (C 1 -C 10 )alkyl group, an aryl moiety (C 6 -C 14 ), a (C 2 -C 8 )carbonyloxyalkyl, and (C 2 -C 8 )carbonyl, and n=1-3.
8. The antireflective coating composition of claim 1 , where the second polymer is a reaction product of an aminoplast with a polyhydroxyl compound.
9. The antireflective coating composition of claim 1 where the aminoplast is selected from structure 19,
where each R 10 is independently CH 2 —O—(CH 2 ) m —CH 3 , m is 0 to 3 and R 11 and R 12 are independently hydrogen or C 1 -C 10 alkyl.
10. The antireflective coating composition of claim 1 where the hydroxyl compound is selected from structures 27 and 28
where R 13 is a spacer group, R 14 is selected from hydrogen, C 1 -C 10 alkyl, an aryl (C 6 -C 20 ), an (C 6 -C 20 )alkylaryl, R 15 , R 16 and R 17 are independently a C 2 -C 8 alkylene spacer.
11. The antireflective coating composition of claim 1 capable of forming a film where the film has a water contact angle in a range of about 65°-85°.
12. The antireflective coating composition of claim 1 capable of forming a film where the film has a contact angle in a range of about 55°-65° in an aqueous alkaline developer.
13. A process for manufacturing a microelectronic device, comprising;
a) providing a substrate with a first layer of an antireflective coating composition from claim 1 ;
b) coating a photoresist layer above the antireflective coating layers;
c) imagewise exposing the photoresist layer with deep ultraviolet exposure;
d) developing the photoresist layer with an aqueous alkaline developing solution.
14. The process of claim 13 , where the first antireflective coating layer has an absorption is value as measured by variable angle spectroscopic ellipsometry in the range of about 0.05 to about 0.35.
15. The process of claim 13 , where the photoresist is sensitive to exposure to radiation of wavelength from about 250 nm to about 12 nm.
16. The process according to claim 13 , where the developing solution is an aqueous solution comprising a hydroxide base.