Patent ID: 8808967

Claim:
A composition suitable for use in forming a topcoat layer over a layer of photoresist, the composition comprising: a matrix resin comprising one or more acidic functional groups; an additive resin that is different from and substantially immiscible with the matrix resin, the additive resin comprising: as polymerized units a first monomer of the formula (I): wherein R 1 is hydrogen or a C1 to C6 optionally substituted alkyl or fluoroalkyl group, R 2 is an optionally substituted cycloalkyl or branched alkyl group, R 3 is an optionally substituted alkylene group and R 4 and R 5 are independently C1 to C4 fluoroalkyl groups; and as polymerized units a second monomer comprising one or more photoacid-labile groups, wherein the second monomer is of the formula (II): wherein R 1 is, independent of R 1 of the first monomer, hydrogen or a C1 to C6 optionally substituted alkyl or fluoroalkyl group; and R 8 is an acid-labile group; wherein the additive resin has a lower surface energy than a surface energy of the matrix resin; and a mixture of solvents comprising a dialkyl glycol monoalkyl ether effective to achieve phase separation of the additive resin from the matrix resin during spin-coating.