Patent ID: 6489590
Filing Date: 2002-12-03
Classification: B23K,H01L

Abstract:
A method of complete laser removal of inorganic and organic foreign material, including particles down to sub-micron sizes and atomic contaminants, including heavy metals and alkaline elements, from a substrate without any damage to the substrate, said method comprising placing the substrate in a process chamber and causing gases to flow through said chamber while irradiating the substrate surface by UV laser irradiation, wherein said gases comprise at least a first reactive gas selected from the group consisting of NO, NO2, N2O3, N2O4, NO3 and NO4, and mixtures thereof, and at least a second gas selected from the group consisting of SF4, NOC1, CF3Cl, Cl2O, and F2O and wherein inorganic and organic foreign material is removed from the substrate surface.