Self-forming top anti-reflective coating compositions and, photoresist mixtures and method of imaging using same

A photoresist formulation, comprising:

• a photoresist polymer;
• at least one photoacid generator;
• a casting solvent;
• and
• a polymer having an ethylenic backbone and comprising a first monomer having an aromatic moiety, a second monomer having a base soluble moiety or an acid labile protected base soluble moiety, and a third monomer having a fluoroalkyl moiety, wherein said polymer has a refractive index of less than about 1.53 with respect to a radiation wavelength of about 193 nm.

A method of forming a patterned material feature, comprising:

• (a) applying a photoresist formulation over a material on a substrate, said photoresist formulation comprising:
• a photoresist polymer;
• at least one photoacid generator;
• a casting solvent;
• and
• a polymer having an ethylenic backbone and comprising a first monomer having an aromatic moiety, a second monomer having a base soluble moiety or an acid labile protected base soluble moiety, and a third monomer having a fluoroalkyl moiety, wherein said polymer has a refractive index of less than about 1.53 with respect to a radiation wavelength of about 193 nm;
• after (a), (b) said photoresist formulation separating to form a top anti-reflective coating and a photoresist layer, said photoresist layer between said anti-reflective coating and said substrate;
• after (b), (c) patternwise exposing said photoresist layer to actinic radiation thereby creating a pattern of radiation-exposed regions in said photoresist layer;
• after (c), (d) selectively removing said antireflective coating and said radiation-exposed regions in said photoresist layer to form openings through said photoresist layer;
• and
• after (d), (e) etching or ion implanting through said openings to form said patterned material features.