Dynamics of Excimer Laser Ablation in Plasma Environments

提出的研究计划是对等离子体和气体环境中紫外准分子激光烧蚀材料动力学的综合实验研究。这将是第一次在预电离等离子体背景下，在从大气到1mtorr的大范围填充气体压力下，研究激光烧蚀的实验。本研究的目的是建立等离子体与气体激光烧蚀加工的知识库，可用于工程应用，如微电子的烧蚀蚀刻，微加工，烧蚀材料合成和燃烧。研究将涉及激光烧蚀物质（等离子体、中性原子和微粒）与背景等离子体与非反应气体的相互作用的两个重要案例，以及等离子体与可以支持氧化、氮化或燃烧的气体的相互作用。物种分辨激光探测诊断测量将进行表征准分子激光烧蚀羽种动力学。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。本研究有完备的实验设备，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，以及广泛的光谱设备。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、制造业和机床工业的制造技术基础。

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.