Patent ID: 7033728

Claim:
A photoresist composition comprising: a) a polymer that is insoluble in an aqueous alkaline solution and comprises at least one acid labile group, and comprises at least one monomer unit having a pendant group selected from unsubstituted or substituted diamantane, triamantane or mixtures thereof; and b) a compound capable of producing an acid upon irradiation, wherein the monomer unit is selected from wherein R 1 is -Z or —Y-Z where Y is a linear or branched alkylene or a monocyclic or polycyclic alkylene, Z is unsubstituted or substituted diamantane, triamantane or mixtures thereof; R 2 , R 3 , and R 4 are each independently selected from hydrogen, alkyl, alkoxyalkyl, cycloalkyl, cycloalkenyl, aryl, aralkyl, and CN or any two of R 2 , R 3 , and R 4 together with the carbon atoms to which they are attached form an unsubstituted or substituted mono- or polycycloalkenyl; X is O or NR 2 .