Simulation of locally enhanced three‐dimensional diffusion in chemically amplified resists

Evidence from simulation, linewidth measurements, and in situ Fourier‐transform infrared (FTIR) data are presented which suggests that a type II diffusion front is moving through positive tone t‐BOC material during postexposure bake. A steady increase in linespace of 50 nm/min is observed in IBM APEX‐E and even faster rates can be found in generic t‐BOC resists. The simultaneous reaction and three‐dimensional deprotection dependent diffusion simulation was carried out with a massively parallel approach. A novel FTIR measurement of transmission versus time of patterned and unpatterned wafers during postexposure bake corroborated scanning electron microscope linewidth measurements.