Patterning on the arbitrary surface for the development of 3D photomask

Micro-patterning on non-planar surfaces is required in the packaging and MEMS fields in order to fabricate new micromechanical devices. In this paper, we propose a new patterning process using a 3D photolithography technique for micro-patterning on a non-planar surface. We also report on the fabrication of a 3D photomask for a substrate using the proposed process. The patterning process is based on a twophoton polymerization laser-writing and lift-off process. We confirmed that fine patterns with line widths down to 2 ?m were successfully formed inside the semi-circular trench. In addition, the transfer of the micro-pattern from the 3D photomask to the cylindrical surface of the fiber substrate was confirmed.