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

Abstract

This paper reports an arbitrary-shape designable 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 lm, 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.

3D-Printed Polymer/Metal Hybrid Microstructures with Ultraprecision for 3D Microcoils

“…The inductance and self-capacitance of a coil can be calculated from its dimensions, forming the number of turns according to the parallel equivalent circuit model using equations [Eqs. (1)(2)(3)]. 20,21…”

“…However, the fabrication of functional 3D microcoils has remained difficult with conventional patterning techniques. [1][2][3][4][5][6] For these reasons, the development of alternative direct 3D patterning techniques to fabricate 3D microcoils, which are useful for compact wireless communication devices, wireless power transmission, and small antennas, has attracted much attention.…”