Laser-induced forward transfer of functional SU-8 microparts

We have developed a robust and universal method to transfer functionalized SU-8 microparts with metallic patterns by laser-induced forward transfer (LIFT) technique. To overcome the difficulty of metal patterning on high-aspect ratio SU-8 microparts on the donor substrate, we utilize a stencil lithography method. The influence of laser energy and SU-8 thickness on the micropart transfer result is systematically studied, and we find the optimized parameter combination to guarantee damage-free transfer. Various transfer examples are displayed to prove that LIFT can not only non-destructively transfer SU-8 functional microparts, but also preserve the functionality after the transfer.