Light-enhanced electroless Cu deposition on laser-treated polyimide surface

Abstract

Laser ablation of polyimide (PI) surface results in the formation of a glassy carbon layer on its surface, especially at near-threshold fluence. Glassy carbon can mediate the electroless metal deposition resulting thus in a local metallization of the surface, as it has been shown recently for the ablated surfaces of PI (cw argon ion laser) and diamond. In the present work, this carbon layer is produced by irradiation of PI in air by a cw Ar + ion laser (wavelength of 514 nm). The ability of this layer to promote the electroless Cu deposition from the corresponding plating solution is studied as the function of laser processing parameters and conditions of deposition. The effect of exposure of the glassy carbon layer to visible radiation on the rate of deposition is studied. The possible mechanisms of the electroless deposition on the glassy carbon are discussed.