Back to results
US 5,314,931 AGranted
Resist compositions
AssigneeShin-Etsu Chemical Co., Ltd.
InventorsMotoyuki Yamada, Tomoyoshi Furihata, Osamu Watanabe, Fujio Yagihashi
Life of this patent
Estimating the term…
Abstract
A resist based on a living polymer is provided. Living anionic polymerization of p-alkoxycarbonylstyrene monomers results in polymers having a molecular weight distribution (Mw/Mn) of from 1 to 1.4.
Claims9
A positive resist composition comprising a polymer, a photo-initiator and an inert organic solvent, said polymer being obtained by living anionic polymerization of at least one monomer having the formula (1):
- ##STR7## where R.sup.1 to R.sup.5 are independently selected from the group consisting of hydrogen and alkyl groups having 1 to 12 carbon atoms, and R.sup.6 is hydrogen or a methyl group;
- said polymer having a molecular weight distribution of from 1.0 to 1.2;
- said photo-initiator being one which is decomposed upon exposure to light to generate a strong acid and to cause cleavage of a group having formula (3) in the living polymer into a group having formula (4), ##STR8## wherein R.sup.1 and R.sup.3 are the same as defined above, thereby converting said polymer into an alkali soluble polymer.
Dependencies are inferred from the claim text.