Dissolution characteristics of chemically amplified 193 nm resists

The dissolution kinetics of two types of chemically amplified positive 193 nm resists were investigated; a ter-polymer resist consisting of poly (tric yclodecylacrylate-co-tetrahydrodpyranyl-methacrylate-co-methacrylic acid) a nd triphenylsulfonium triflate as a photoacid generator, and a copolymer re sist consisting of poly(carboxytetracyclododecylmethacrylate-co-tetrahydrop yranyloxy-carbonyl-tetracyclododecylmethacrylate) and triphenylsulfonium tr iflate as a photoacid generator. The dissolution rate contrast was higher a nd the slope of dissolution rate curve was steeper for the ter-polymer resi st than those for the copolymer resist. However, the Arrhenius plots of the dissolution rates were straight lines for both resists irrespective of the exposure doses. This indicates that only one mechanism determines the diss olution of both resists, and it is believed that the dominant rate-determin ing step in both resists is the tetramethylammoniumhydroxide penetration in to the resist films. The resolution capability of the ter-polymer resist wa s very high, 0.14 mu m Lines and spaces pattern. The resolution capability of the copolymer resist was moderate, 0.16 mu m lines and spaces in spite o f its lower dissolution contrast and smiler slope value. In addition, the d ry-etch resistance of both resists was close to that of a conventional poly hydroxystyrene base KrF resist. These results indicate that both the ter-po lymer and the copolymer resists are candidates for practical use. (C) 1998 American Vacuum Society. [S0734-211X(98)09406-2].