Microstructure, magnetic-dielectric properties of flexible composite film for high frequency applications

Flexible electronics is attracting widely interests for next generation electronics, especially for RF application. In this work, a flexible composite film with good magnetic-dielectric properties at high frequency was synthesized. Firstly, we prepared NiCuZn ferrite particles with uniform grains (similar to 1.57 pm) at low temperature. Results indicated that the ferrite possessed high permeability (mu(r)' = 472.8), low loss (tan delta(mu) = 0.015 and tan delta(epsilon) = 0.0063) and high saturation magnetization (M-s = 61.77 emu/g). The flexible composite films were prepared by mixing the NiCuZn particles and PDMS. The microstructures, high frequency magnetic and dielectric properties of the composite films with various NiCuZn particles were investigated. Results indicated that the NiCuZn particles not only can uniformly blend with PDMS, but also improve magnetic properties of the PDMS film at high frequency. At last, the flexible composite film possessed good magnetic properties (mu(r)' = 2.09 and tan delta(mu) = 0.47) and dielectric properties (epsilon(r)' = 4.43 and tan delta(epsilon) = 2.32e-2) at 1 GHz. It was indicated that the flexible film can be utilized for high frequency flexible devices. The method is also a reference for developing high frequency wearable electronic devices.