Selective patterning of indium tin oxide films using 1064 nm laser for microparts processing

Abstract

Conventional metal microparts were fabricated by a series of complex photolithography, sputtering, sacrificial layer and release processes. This reported work demonstrates the integrated process of metal microparts using 1064 nm Nd:YVO4 laser direct-write patterning of indium tin oxide (ITO) thin films on glass, followed by the electrochemical deposition of copper (Cu) on the pattern. The ITO thin film could be removed without any damage to the glass structure through the diffractive multiple Nd:YVO4 beam. A high overlapping area of the laser spot was used to pattern the electrode layer on the film surface for obtaining a 50 µm ablated edge profile with a linear boundary after laser patterning. A high quality of surface could be achieved at a proper parameter control without numerous processing steps. Compared with conventional photolithography and etching technologies, direct-write micropatterns of ITO using the Nd:YVO4 laser is a maskless, dry and low-cost process. Accordingly, the micrometal parts can be obtained using the electrochemical deposition and release process of laser-patterned ITO films because of the adhesion property of Cu on ITO.