GEL FORMATION THEORY APPROACH FOR THE MODELING OF NEGATIVE CHEMICALLYAMPLIFIED E-BEAM RESISTS

Gel formation theory is applied for the interpretation of experimental lithographic results of epoxy based negative e-beam resists. The succ ess of different theoretical models in fitting experiments depends upo n the value of concentration of the photoacid generator (PAG) and the thermal processing conditions. The chemical composition of each specif ic system, the sensitivity and the range of acid diffusion are importa nt parameters in the analysis. It is concluded that existing theories with an appropriate interpretation explain satisfactorily experimental results in a given range of resist composition and processing paramet ers. However in some cases a model which would include more explicitly the reaction-diffusion mechanism is required.