Novel negative photoresist based on polar alicyclic polymers for ArF excimer laser lithography

A new polar alicyclic polymer has been developed as an ArF negative resist polymer. Poly(carboxytetracyclo[4.4.0.1^2,51^7,10] dodecyl acrylate-hydroxytricyclo[5.2.1.0^2,6]decyl acrylate (polyCTCDDA_m-TCDAOH_n)) has carboxyl and hydroxyl groups. It was founded that reactivity of the hydroxyl group was much higher than that of the carboxyl group in the acid- catalyzed crosslinking reaction. Poly(CTCDDA₃₂-TCDAOH₆₈) exhibits good solubility (0.5 micrometers /sec) in the standard developer (2.38% TMAH aq.), high transparency (70%/0.5 micrometers ) at 193-nm and high thermal stability (decomposition point: 230 degree(s)C). A chemically amplified negative resist composed of this polymer and 1,3,4,6- tetrakis(methoxymethyl)glicoluril (TMGU) provided a resolution of 0.18-micrometers L/S pattern with an ArF exposure system (NA equals 0.55) at a 9.2 mJ/cm² dose.