Effect of temperature variation during post exposure bake on 193 nm chemically amplified resist simulation

We measured the temperature change of 193 nm chemically amplified resist during post exposure bake and investigated the effects of these variations on photoresist (PR) simulation. The effects of the variations were studied for various baking and cooling methods. The effective PEB time was determined by considering the temperature variation during PEB. The effective PEB times were used in simulation and the resulting PR profiles were compared with the experimental results. The resulting profiles showed a significant variation in line width depending on bake conditions. Careful PEB temperature consideration is necessary since the resulting line width is strongly dependent on the resist temperature rising and cooling rate. The effective bake time with proper consideration of the temperature change during PEB should be used in the simulation to depict experimental profile correctly.