Abstract
The time resolved transmission of P10, poly(methyl methacrylate), resist films has been studied during ablative photodecomposition (APD) by KrF, KrCl, and ArF excimer lasers. The observed changes in transmission are most likely due to scattering and absorption by the ablated material during and after the laser pulse. Measurements of the energy per unit volume absorbed at the threshold laser fluence for APD as a function of wavelength indicate that APD is not caused solely by a thermal degradation process.