Fabrication of three-dimensional micro-Rogowski coil based on femtosecond laser micromachining

摘要

This paper reports an arbitrary-shape des-ignable fabrication of three-dimensional (3D) micro-Rogowski coil inside silica glass by means of femtosecond laser wet etches and metal microsolidics. The dimension of the fabricated micro-Rogowski coil is 800 μm, and the aspect ratio of the structure reaches about 300. The alloys of Bi/In/Sn/Pb with high melting point were used as the conductive metal. The inductance of micro-Rogowski coil is 113.58 nH at 10 kHz and 14.11 nH at 120 MHz, respectively. The embedded 3D micro-Rogowski coils can be easily integrated with other microelectrical, mechanical and optical systems, which could be widely applied in MEMS, sensors and lab-on-chips.