Fabrication of robust metallic micropatterns on glass surfaces by selective metallization in laser-induced porous surface structures

Conductive metallic micropatterns on transparent glass substrates are desired in lots of applications, e.g. electrofluidic devices and micrototal analysis systems. Due to the significant differences in material properties between metal and glass, the fabricated metallic micropatterns prone to show limited bonding strength to the glass substrates. In this paper, microgrooves with porous edge areas are prepared by a laser-induced backside wet etching (LIBWE) method. In the subsequent electroless plating process, this peculiar surface structure enables fast deposition of copper on these areas without further treatment of the surface. Moreover, due to the strong anchor effect caused by the porous microstructures, the obtained copper micropatterns show high bonding strength to the glass substrate. No damage or peeling is observed under 20-min sonication in water and repeated scotch tape test. These micropatterns can even survive from surface polishing by sandpapers. We also demonstrated that this copper micropatterns with low resistivity (1.9 mu Omega.cm) could be used for rapid heating of localized surface areas, which may be a potential choice for various microsystems.