Three-dimensional microcoils as terahertz metamaterial with electric and magnetic response

Abstract

A metamaterial consisting of three-dimensional submillimeter solenoidal coils is presented. The structures have been fabricated by an automated wire-bonding technique and are characterized by terahertz time-domain spectroscopy and numerical simulations. We demonstrate the excitation of electric and magnetic resonances in the microcoils at frequencies between 0.05 and 0.6 THz. The implementation of these microstructures provides a promising route for the design of nonplanar and intrinsically chiral metamaterials for gigahertz to terahertz frequencies.

Unconventional applications of wire bonding create opportunities for microsystem integration

“…This points the way towards unique metamaterial structures, as demonstrated by [84], reporting on a large and regular array of microcoil resonators (Table 2-f). Because of the chirality of each coil (which planar coils do not have), the metamaterial resonance constructively interferes with the incoming RF wave to cause a phase shift among the perpendicular electric and magnetic field phasors, so that the propagating wave is thereby circularly polarized.…”

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

“…However, these methods always require expensive equipments and have complicated procedures. Although the straight solenoid microcoils can be made by winding metal microwire around pillars [16,17], the method is difficult to fabricate complex solenoid microcoils, such as micro-Rogowski coils [18].…”

Investigation of on-chip integrated inductors fabricated in SOI-MUMPs for RF MEMS ICs

“…Alternatively, Microelectromechanical systems (MEMS) inductors offer better performance in terms of the Q-factor and selfresonance frequency (SRF) [7]. Furthermore, unlike CMOS inductors, which are confined to planar structures, MEMS inductor offers various geometrical structures, such as planar inductor [8,9] solenoid inductor [10], 3D inductors [11], and vertical inductors [12]. However, these inductors involve complex and high cost fabrication process, which undermines their performance advantage.…”