Dynamics of Excimer Laser Ablation in Plasma Environments

提出的研究计划是一项关于紫外准分子激光在等离子体和气体环境中烧蚀材料的动力学的综合实验研究。这将是第一次在从大气压到1mTorr的广泛填充气体压力范围内研究预电离等离子体背景下的激光烧蚀。本研究的目的是为微电子设备的烧蚀、微机械加工、烧蚀材料的合成和燃烧等工程应用建立一个等离子体和气体激光烧蚀的知识库。研究涉及激光烧蚀物质(等离子体、中性原子和微粒)与1)背景等离子体与非反应气体的相互作用，以及2)等离子体与支持氧化、氮化或燃烧的气体的相互作用的两个重要案例。将进行物种分辨激光探测诊断测量，以表征准分子激光烧蚀羽流的物种动力学。激光烧蚀辅助放电实验将适用于材料的快速加热、烧蚀和电离。这项研究有完整的实验设施，包括：准分子激光器(KrF和XeCl)、染料激光器、CO2激光器、红宝石激光器和铜蒸气激光器，以及广泛的光谱设施。在这项研究中获得的知识可能会导致材料加工和合成技术的突破。任何发现都将扩大微电子、光电子、制造和机床行业的制造技术基础。

The proposed research program is a comprehensive experimental investigation of the dynamics of ultraviolet excimer laser ablation of materials in plasma versus gas environments. These will be the first experiments to investigate laser ablation in pre-ionized plasma backgrounds over a wide range of fill gas pressure, from atmospheric to 1 mTorr. The objective of this research is to develop a knowledge base on laser ablation processing in plasmas versus gases which can be usef for engineering applications, such as ablative etching of microelectronics, micromachining, ablative material synthesis, and combustion. Research will be performed on two important cases concerning interaction of laser-ablated matter (plasma, neutral atoms, and particulates) with 1) background plasmas versus gases which are nonreacting, and 2) plasmas versus gases which can support oxidation, nitriding, or combustion. Species-resolved laser probing diagnostic measurements will be performed to characterize excimer laser ablation plume species dynamics. Laser-ablation-assisted-discharge experiments will be performed with applicability to rapid-heating, ablation and ionization of materials. Complete experimental facilities exist for this research, including: excimer lasers (KrF and XeCl), dye laser, CO2 laser, ruby lasers, and copper vapor laser, as well as extensive spectroscopic facilities. The knowledge obtained in this research could lead to breakthroughs in materials processing and synthesis techniques. Any discoveries will expand the technology base for fabrication in the micro- electronics, opto-electronics, manufacturing, and machine tool industries.