Self-segregating multilayer imaging stack with built-in antireflective properties
View Patent ↗A coating process comprises forming a patterned material layer on a substrate using a self-segregating polymeric composition comprising a polymeric photoresistive material and an antireflective coating material. The polymeric photoresistive material and the antireflective coating material that make up the self segregating composition are contained in a single solution. When depositing this solution on a substrate and removing the solvent, the two materials self-segregate into two layers. The substrate can comprise one of a ceramic, dielectric, metal, or semiconductor material and in some instances a material such as a BARC material that is not from the self segregating composition. The composition may also contain a radiation-sensitive acid generator and a base quencher. This produces a coated substrate having a uniaxial bilayer coating oriented in a direction orthogonal to the substrate with a top photoresistive coating layer and a bottom antireflective coating layer. The process may also include optionally coating a top coat material on the coated substrate. Pattern-wise exposing the coated substrate to imaging radiation and contacting the coated substrate with a developer, produces the patterned material layer wherein the optional top coat material and a portion of the photoresist layer are simultaneously removed from the coated substrate, thereby forming a patterned photoresist layer on the substrate. Alternatively, the optional top coat material, a portion of the photoresist layer and a portion of the bottom antireflective layers are simultaneously removed from the coated substrate by the developer, thereby forming a patterned photoresist layer on the substrate.
1. A method of forming a patterned material layer on a substrate, said method comprising:
(a) providing a substrate;
(b) forming a layer of a self-segregating polymeric composition on said substrate, where said self-segregating polymeric composition comprises;
i. a polymeric photoresistive material comprising a positive working photoresist or a negative working photoresist,
ii. a polymeric BARC material,
iii. an optional radiation-sensitive acid generator and,
iv. an optional base quencher,
to form a coated substrate comprising a uniaxial bilayer polymer coating on and substantially parallel to said substrate, said uniaxial bilayer polymer coating undergoing a phase separation that is oriented in a direction orthogonal to said substrate, said coated substrate thereby including a top photoresistive coating layer and a bottom antireflective coating layer;
(c) optionally, forming a layer comprising a top coat material on said uniaxial bilayer;
(d) pattern-wise exposing said coated substrate to imaging radiation to form a patterned area comprising exposed areas and unexposed areas, and optionally an area not covered by a pattern;
(e) optionally, baking the exposed substrate; and
(f) contacting said coated substrate with a developer; wherein said antireflective coating comprises a silicon polymer having the general structure:
where (SiO 1.5 ) comprises a polysilsesquioxane polymer backbone, R 1 and R 2 independently comprise a linear, branched, or cyclic alkylene group of 1 to about 10 carbons, A is either hydrogen, methoxy-, ethoxy or other alkoxy-, halogen or an ester group, B is hydroxy-, carboxy or a carboxamido-group and is independently located in the 2-, 3- or 4-positions of the benzene ring, C is a nonaromatic moiety comprising:
where D and E independently are hydrogen, hydroxy-, acetoxy-groups, alkylalkoxy- or alkylacetoxy-groups or D and E can form a cyclic epoxide, the molar fractions x, y and z independently represent a value from 0 to about 0.8 and the sum of x, y and z equals 1 or
wherein said antireflective coating comprises an amide polymer having a general structure:
where R 3 is a linear, branched, or cyclic alkylene group of 1 to about 10 carbons, G is hydrogen, hydroxy-, acetoxy-, methoxy-, ethoxy- or other alkoxy-, halogen, ester, carboxy- or a carboxamido-group, J is alkyl, alkoxy-, or up to about 6 carbon atom carboalkoxy or alkoxycarbonyl esters, lactone or anhydride moieties, the molar fractions x, y and z independently are from 0 to about 0.5 and the sum of x, y and z equals 1, and the amide group is an organic amidic group:
where R can be methyl, ethyl, phenyl or vinyl and R′ and R″ can be independently hydrogen, alkyl, or an aryl group.
2. The method of claim 1 wherein said polymeric photoresistive material comprises a positive working photoresist, said method further including forming a layer comprising a top coat material on said uniaxial bilayer, and the developer in step (f) comprises a developer selected to dissolve all of said top coat and only the exposed parts of said positive working photoresist.
3. The method of claim 1 wherein said polymeric photoresistive material comprises a positive working photoresist, said method further including forming a layer comprising a top coat material on said uniaxial bilayer, and the developer in step (f) comprises a developer selected to dissolve all of said top coat, the exposed parts of said positive working photoresist, and portions or all of said bottom antireflective coating layer in said exposed areas.