New photoresists are needed to advance extreme ultraviolet (EUV) lithography. The tailored design of efficient photoresists is enabled by a fundamental understanding of EUV induced chemistry. Processes that occur in the resist film after absorption of an EUV photon are discussed, and a new approach to study these processes on a fundamental level is described. The processes of photoabsorption, electron emission, and molecular fragmentation were studied experimentally in the gas-phase on analogs of the monomer units employed in chemically amplified EUV resists. To demonstrate the dependence of the EUV absorption cross section on selective light harvesting substituents, halogenated methylphenols were characterized employing the following techniques. Photoelectron spectroscopy was utilized to investigate kinetic energies and yield of electrons emitted by a molecule. The emission of Auger electrons was detected following photoionization in the case of iodo-methylphenol. Mass-spectrometry was used to deduce the molecular fragmentation pathways following electron emission and atomic relaxation. To gain insight on the interaction of emitted electrons with neutral molecules in a condensed film, the fragmentation pattern of neutral gas-phase molecules, interacting with an electron beam, was studied and observed to be similar to EUV photon fragmentation. Below the ionization threshold, electrons were confirmed to dissociate iodo-methylphenol by resonant electron attachment.

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对极端抗紫外线材料化学过程的基本了解

需要新的光刻胶来推进极紫外（EUV）光刻。通过对EUV诱导化学的基本了解，可以进行有效的光致抗蚀剂量身定制的设计。讨论了EUV光子吸收后在抗蚀剂膜中发生的过程，并描述了一种从根本上研究这些过程的新方法。在气相中，对化学放大的EUV抗蚀剂中使用的单体单元的类似物进行了实验研究，研究了光吸收，电子发射和分子断裂的过程。为了证明EUV吸收截面对选择性光收集取代基的依赖性，采用以下技术对卤代甲基苯酚进行了表征。利用光电子能谱研究分子的动能和电子发射率。在碘甲基苯酚的情况下，在光电离之后检测到俄歇电子的发射。质谱用于推导电子发射和原子弛豫后的分子碎裂途径。为了深入了解冷凝膜中发射电子与中性分子的相互作用，研究了中性气相分子与电子束相互作用的碎裂模式，发现该模式类似于EUV光子碎裂。在电离阈值以下，通过共振电子附着确认电子解离了碘代甲基苯酚。质谱用于推导电子发射和原子弛豫后的分子碎裂途径。为了深入了解冷凝膜中发射电子与中性分子的相互作用，研究了中性气相分子与电子束相互作用的碎裂模式，发现该模式类似于EUV光子碎裂。在电离阈值以下，通过共振电子附着确认电子解离了碘代甲基苯酚。质谱用于推导电子发射和原子弛豫后的分子碎裂途径。为了深入了解冷凝膜中发射电子与中性分子的相互作用，研究了中性气相分子与电子束相互作用的碎裂模式，发现该模式类似于EUV光子碎裂。在电离阈值以下，通过共振电子附着确认电子解离了碘代甲基苯酚。被研究并观察到与EUV光子碎裂相似。在电离阈值以下，通过共振电子附着确认电子解离了碘代甲基苯酚。被研究并观察到与EUV光子碎裂相似。在电离阈值以下，通过共振电子附着确认电子解离了碘代甲基苯酚。