Model for polymerization and self-deactivation in two-photon nanolithography
Model for polymerization and self-deactivation in two-photon nanolithography
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DOI：
10.1364/oe.461969
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发表时间：
2022-07-18
期刊：
影响因子：
3.8
通讯作者：
Xu, Xianfan
中科院分区：
文献类型：
--
作者：
Johnson, Jason E.;Chen, Yijie;Xu, Xianfan
建立了一个数学模型来描述双光子纳米光刻中的光化学过程，包括两步吸收导致光引发剂的引发和自失活，聚合物链的增长、终止、抑制以及抑制剂和光引发剂的扩散.该模型被数值求解，以获得作为时间和空间的函数的反应物质的浓度，作为激光束被扫描通过一定体积的光致抗蚀剂，由此确定体素尺寸或线宽。最具影响力的工艺参数是通过将模型拟合到一系列激光功率和扫描速度的实验测量线宽来确定的，同时还获得了与先前测量值相似的有效非线性。不同的工艺参数的影响和灵敏度进行检查。结果表明，光聚合过程中的光引发剂和氧抑制剂的扩散占主导地位，自失活可以导致更高的有效非线性双光子纳米光刻。(C)2022 Optica出版集团根据Optica开放获取出版协议的条款
A mathematical model is developed to describe the photochemical processes in two-photon nanolithography, including two-step absorption leading to initiation and self-deactivation of the photoinitiator by laser irradiance, polymer chain propagation, termination, inhibition, and inhibitor and photoinitiator diffusion. This model is solved numerically to obtain the concentrations of the reaction species as a function of time and space as a laser beam is scanned through a volume of photoresist, from which a voxel size or linewidth is determined. The most impactful process parameters are determined by fitting the model to experimentally measured linewidths for a range of laser powers and scanning speeds, while also obtaining effective nonlinearities that are similar to previously measured values. The effects and sensitivities of the different process parameters are examined. It is shown that the photopolymerization process is dominated by diffusion of photoinitiators and oxygen inhibitors, and that self-deactivation can lead to higher effective nonlinearities in two-photon nanolithography. (C) 2022 Optica Publishing Group under the terms of the Optica Open Access Publishing Agreement