Laser induced selective electroless copper plating on polyurethane using EDTA-Cu as active material

Abstract

Using EDTA-Cu as the active material and polyurethane as the matrix, flexible cathodes were fabricated by laser-induced electroless copper plating process (LPKF-LDS) and characterized by SEM, X-ray energy spectrum and Auger electron spectroscopy. Flexible cathodes prepared from EDTA-Cu and polyurethane showed good selectivity in copper plating process. Composition and particle morphology of EDTA-Cu, laser power, scanning speed, laser wavelength, laser spot size, pulse frequency etc. are the main factors that affect the fineness of electroless copper plating. By adjusting these parameters, the fineness of the copper plating was improved. X-ray energy spectrum and Auger electron spectroscopy results showed that after the laser scanning, both Cu^0 and Cu^(+1) appeared in the scanning area, revealing thus the mechanism of electroless copper plating for polyurethane-EDTA-Cu flexible cathodes.