Through pitch line width difference minimization by pixel source optimization

Abstract

Through the adoption of EUV lithography and an increase in numerical aperture (NA), smaller and more complex patterns can now be achieved through single exposure while significantly enhancing throughput. However, due to the variations in pattern shapes and densities, optical proximity correction (OPC) is required, leading to increased computational costs. This study aims to reduce line width variation on wafers and minimize OPC through source optimization. The process was performed under 0.33NA and 0.55NA conditions with a low-n absorbent material. The target pattern was a line and space pattern, focusing on making the same line width among various pitches. High pattern fidelity could be achieved by optimizing the source, while maintaining sufficient imaging performance. © 2024 SPIE.