ABSTRACT
The correction accuracy of a model-based OPC（MB-OPC）depends critically on its edge offset calculation scheme. In a normal MB-OPC algorithm, only the impact of the current edge is considered in calculating each edge offset. As the k1 process factor decreases and design complexity increases, however, the interaction between the edge segments becomes much larger. As a result, the normal MB-OPC algorithm may not always converge or converge slowly. Controlling the EPE is thus become harder. To address this issue, a new kind of MB-OPC algorithm based on MEEF matrix was introduced which is also called matrix OPC. In this paper, a variant of such matrix OPC algorithm is proposed which is suitable for kernel-based lithography models. Comparing with that based on MEEF matrix, this algorithm requires less computation in matrix construction. Sparsity control scheme and RT reuse scheme are also used to make the correction speed be close to a normal one while keeping its advantages on EPE control.
Keywords：OPC, Convergence, Matrix, Low-k1 lithography
