Three-dimensional metallic microcomponents achieved in fused silica by a femtosecond-laser-based microsolidifying process

Three-dimensional (3D) metallic microdevices have attracted a wide attention in the field of functional microsystems, but the fabrication of 3D metallic structures remains a technical challenge. In this study, a femtosecond-laser-based microsolidifying method was employed to fabricate 3D metallic structures by injecting liquid metal into complex 3D microchannels/cavities in fused silica and solidifying the liquid metal. 3D microchannels/cavities, which were served as micromoulds of the metallic microcomponents, were fabricated in fused silica by taking full advantage of the improved femtosecond laser irradiation followed by chemical etching (FLICE) technology. A PDMS-glass injection device was employed to finish the injection of liquid metal and solidification process. This technology will enable the maskless and facile fabrication of complex true-3D metallic conductive microcomponents for a wide array of micro-applications.