Proximity effect correction in electron-beam lithography based on computation of critical-development time with swarm intelligence

Abstract

Electron-beam lithography (EBL) is an important technique in manufacturing high-resolution nanopatterns for broad applications. However, the proximity effect in EBL can degrade the pattern quality and, thus, impact the performance of the applications greatly. The conventional proximity effect correction (PEC) methods, which employ computationally intensive cell or path removal method for development simulation, are very computational lengthy, especially for complex and large-area patterns. Here, the authors propose a novel short-range PEC method by transforming the evaluation of pattern feasibility into the shortest path problem based on the concept of critical-development time. The authors combine this evaluation algorithm with the swarm intelligence which mimics the natural collective behavior of animals to optimize the design of electron dose distribution in EBL. The PEC algorithm is applied for pattern fabrication for U-shaped split-ring resonator and produces optimized exposure pattern that shows excellent agreement with the targeted objectives. Our work on the PEC strategy reduces the computational cost significantly and is particularly suitable for the design of complex pattern with various constraints.