Hybrid algorithm for reducing mask complexity in inverse lithography technique

초록

Inverse lithography technique (ILT) was proposed as efficient means of generating optical proximity correction (OPC) pattern which is one of resolution enhancement technique (RET) [1], and its optimization process has been performed by simulated annealing (SA) [2], genetic algorithm [3], and gradient-based searches [4]. Though ILT can be applied for optimizing any kinds of mask patterns, however, it is not easy to fabricate the optimally generated mask patterns actually because of their complicate structures. Accordingly, several methods for reducing the mask complexity have been tried by introducing an additional complexity penalty term [4], topological constraint [5], or by using bacteria algorithm [6]. In this paper, ILT with the hybrid optimization algorithm was proposed for generating a mask pattern with less mask complexity. The hybrid algorithm is based on combination of SA with bacteria algorithm.