Molecular simulation of photoresists II: application to PAC diffusion

Recent advances in computer hardware and software have provided the capability to simulate complex mixtures of compounds on a molecular level. These tools provide the potential for exploration of resist chemistry and mechanism on a molecular level with visual feedback. Molecular simulations of a DNQ novolac resist were used in an unsuccessful attempt to visualize and study PAC diffusion during PEB. Simulation of PAC molecules allowed the calculation of the Connolly surface and hence the volume of space occupied by the PAC molecule. A reasonable correlation of the Connolly volume with the decrease in standing waves after PEB as measured from DRM curves was observed. This supports a PAC diffusion mechanism for PEB reduction of standing waves.