Quantitative analysis and modeling of line edge roughness in near-field lithography: toward high pattern quality in nanofabrication

Nanophotonics

article

Dandan Han¹  Changhoon Park¹  Seonghyeon Oh¹  Howon Jung¹  Jae W. Hahn¹ 

[1] Nano Photonics Laboratory, School of Mechanical Engineering, Yonsei University

关键词: line edge roughness;    near-field lithography;    surface plasmon waves;    image log-slope;    resist contrast;    point-spread function;   

DOI  :  10.1515/nanoph-2019-0031

学科分类：社会科学、人文和艺术（综合）

来源: De Gruyter

【 摘 要 】

Quantitative analysis of line edge roughness (LER) is very important for understanding the root causes of LER and thereby improving the pattern quality in near-field lithography (NFL), because LER has become the main limiter of critical dimension (CD) control as the feature size of nanostructures is scaled down. To address this challenge, the photoresist point-spread function of NFL with a contact plasmonic ridge nanoaperture can be employed to account for the physical and chemical effects involved in the LER-generation mechanism. Our theoretical and experimental results show that the sources of LER in NFL mainly come from the aerial image, material chemistry, and process. Importantly, the complicated decay characteristics of surface plasmon waves are demonstrated to be the main optical contributor. Because the evanescent mode of surface plasmon polaritons (SPPs) and quasi-spherical waves (QSWs) decay in the lateral direction, they can induce a small image log-slope and low photoresist contrast, leading to a large LER. We introduce an analytical model and demonstrate the relationship between LER and CD to estimate the pattern quality in NFL. We expect that these results can provide alternative approaches to further improve pattern uniformity and resolution, which can lead to advanced nanopatterning results in NFL.

【 授权许可】

CC BY