Synthesis and lithographic evaluation of poly[(methacrylic acid tert-butyl cholate ester)-co-(γ-butyrolactone-2-yl methacrylate)]

Abstract Poly[(methacrylic acid tert-butyl cholate ester)-co-(γ-butyrolactone-2-yl methacrylate)] was synthesized and evaluated as a new 193-nm chemically amplified photoresist. This polymer showed good thermal stability up to 240 °C and had a good transmittance at 193 nm. This material showed good resistance to CF4-reactive ion etching. The resist patterns of 0.15 μm feature size were obtained at a dose of 11 mJ cm−2 using an argon fluoride excimer laser stepper.