Polymerization Photoinitiators with Near-Resonance Enhanced Two-Photon Absorption Cross-Section: Toward High-Resolution Photoresist with Improved Sensitivity
Polymerization Photoinitiators with Near-Resonance Enhanced Two-Photon Absorption Cross-Section: Toward High-Resolution Photoresist with Improved Sensitivity
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DOI：
10.1021/acs.macromol.0c01518
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发表时间：
2020-11-10
期刊：
影响因子：
5.5
通讯作者：
Monnereau, Cyrille
中科院分区：
文献类型：
--
作者：
Arnoux, Caroline;Konishi, Tatsuki;Monnereau, Cyrille
我们利用三阶非线性响应的近共振增强来设计具有优化效率的双光子聚合光引发剂。我们详细研究了它的线性和共振三阶非线性光学性质，特别是光诱导自由基的产生。外围取代基的仔细选择使得其能够直接溶解到商业多官能丙烯酸单体的混合物中，从而在简单混合时产生具有良好光学透明度的均匀光致抗蚀剂。当经受532 nm的亚纳秒脉冲激光照射时，所得光致抗蚀剂显示出比用经典使用的双光子引发剂获得的聚合阈值低多达八倍的聚合阈值，在250 nm的线间间隔处产生亚100 nm的线宽，并导致高度限定的三维结构。
We take advantage of the near-resonant enhancement of the third-order nonlinear response to engineer a two-photon polymerization photoinitiator with optimized efficiency in regard to literature benchmarks. We study in detail its linear and resonant third-order nonlinear optical properties, with particular focus on photoinduced radical generation. Careful choice of peripheral substituents enables its direct solubilization into a mixture of commercial multifunctional acrylic monomers, resulting in a homogeneous photoresist with good optical transparency upon simple mixing. When submitted to sub-nanosecond pulsed laser irradiation at 532 nm, the resulting photoresist displays a polymerization threshold up to eight times lower than that obtained with the classically used two-photon initiators, giving rise to sub-100 nm line width at 250 nm interline separation and resulting in highly defined three-dimensional structures.