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.
