Stochastic Simulation of Development Process in Electron Beam Lithography

We have developed a stochastic simulation of the pattern formation process for positive type resists in electron beam lithography that introduces an improved model of the development process. In the model, the resist dissolved in order from the surface to the substrate, and the dissolution probability of the resist molecules depended on the molecular weight. The development characteristics obtained by the simulation was evaluated for Poly(methyl methacrylate) resist. The improved simulation made it possible to reproduce the time-dependent development process of the resist. The dependences of resist molecular weight, development time, and exposure dose on the development obtained by simulation was quantitatively evaluated by comparing with the experimental results.