UV-laser-induced etching and metal seeding on polymers; a surface characterization

Results of UV (308 nm) laser pulse induced dry etching with subsequent Pd d eposition from a PdCl2 solution (acid base with pH =1) on polyimide surface are reported. The surface roughness has been determined before and after i llumination. The fractal-based examination techniques based on the area-per imeter and the structure function methods. It could be concluded that the p reetching of the polyimide surface significantly enhances the flux of Pd at oms deposited onto the surface, which is a power function of the number of shots (30 mJ/cm(2) at 20 ns pulse duration) with a power coefficient close to 0.5. It has been observed that the seeding process started simultaneousl y at a number of places resulting in island-like deposits. Fractal characte risation of surfaces resulted in a fractal dimension changing between 2.28 and 2.71 carried out with the methods outlined earlier. It might be conclud ed that the seeding process occurs at atomic scale, but it exhibits a very strong trend towards the formation of aggregates and/or cluster-type struct ures. (C) 1999 Elsevier Science B.V. All rights reserved.