A theoretical description of ultraviolet laser ablation of organic materials

A theoretical description of the ultraviolet laser etching process is developed. The model is based on an analysis of radiation transport at high intensities, and the results agree well with all available experimental etch data for organic polymers. In its simplest form the model describes ablation by single-photon absorption of the laser light, with negligible attenuation of the laser pulse by the ablation plume. This would describe ablation of a material with a relatively high single-photon absorption coefficient and with ablation products which do not strongly absorb at the laser wavelength. The calculated curve correlates excellently with the measured ablation data for XeCl excimer laser etching of polyimide. The concepts involved should be applicable to the description of excimer laser ablation of tissues