3D replication using PDMS mold for microcoil

In this study, a novel fabrication method for fabricating complicated three-dimensional (3D) microcoil structures involving pre- and post-process was developed. As the pre-process, a 3D replication method using polydimethylsiloxane (PDMS) mold was developed for simple and low-cost fabrication of microstructures. The 3D PDMS mold was easily fabricated by using PDMS as the mold material. A master pattern with a microcoil structure was accurately transferred to a mold cavity shape. Within the cavity of the 3D PDMS mold, an ultraviolet (UV) curable resin structure was precisely replicated along the surface of a cylindrical Al wire deposited with Au-Ti. This replicated UV resin replica was utilized as the base component for the fabrication of a microcoil structure by electroplating. Finally, a microcoil structure with an outer diameter of 537.9 μm, line width of 12.3 μm, and coil thickness of 8.2 μm was fabricated by a post-process including electroplating.