9504102 Molian The feasibility of a novel femtosecond pulsed excimer laser processing technique for precision machining of chemical vapor deposition (CVD)-diamond films will be investigated. Femtosecond pulsed laser ablation of diamond is expected to be significantly different from that of currently practiced nanosecond or longer-pulsed laser ablation because of its capability to provide extreme intensities and larger absorption depth/thermal diffusion distance ratios. Femtosecond lasers can offer an entirely new spectrum of laser-diamond interactions that can alter dynamics of ablation products (energy and mass distribution), nature of particle emission (ionized, neutral, etc.) and associated phenomena namely plasma formation and shock propagation. Consequently, there will be a greater degree of atomization of material to be removed, reduced thermal component of ablation, absence of clusters and particulates on the machined surfaced, and less probability for the transformation of diamond to graphite. Such effects ultimately lead the proposed machining technique to be a high precision, contamination-free, time efficient procedure for craggy CVD-diamond films that requires low bulk temperature during machining. It is anticipated that this novel laser processing scheme will not only refine the existing laser-processing techniques but also surpass all other diamond micromachining techniques and, additionally, generate new applications in other areas of research such as deposition of thin films.
