New advances and steam laser cleaning of opaque and transparent critical substrates: with IR-lasers to new laser cleaning mechanism

摘要

Dry and steam laser cleaning, DLC and SLC, of nano-and micro-contaminant particles from UV/vis opaque and transparent critical substrates has been studied in front-side laser illumination geometry with the help of time-resolved optical techniques using a nanosecond IR CO_2-laser and different energy transfer media (ETM) fluids. In the case of SLC, microscopic details of particle-ETM-substrate interactions in pre-deposited micron-thick ETM layers have been revealed preliminarily by means of time-resolved optical microscopy. Fundamental DLC and SLC mechanisms for removal of nano- and micro-particles from opaque and transparent critical substrates have been determined. Optimal conditions for nearly complete laser cleaning have been chosen for different combinations of contaminating nano- and micro-particles and substrates.