Substrate type and their rotation speed controlled magnetic anisotropy of iron films evaporated by a newly designed vacuum coating system

Abstract

A newly designed Vacuum Coating System (VCS) system has been used for the first time to prepare magnetic iron thin films on plastic kapton and rigid glass substrates at different rotation speeds (0 rpm, 30 rpm, 60 rpm, and 90 rpm). The powdered iron as a source material was evaporated by a resistively heated furnace positioned right under the substrate within the VCS system. Magnetic measurements showed that an in-plane magnetic anisotropy exist in all films. The films deposited on flexible kapton show that the degree of uniaxial magnetic anisotropy and coercivity decreased with decreasing rotational speed. For glass substrates used at low speeds (0 rpm and 50 rpm) magnetic isotropy was observed and coercivity was found to be almost constant while a slight anisotropy and a small change of coercivity was observed at 90 rpm. Coercivity of the films deposited on kapton substrates was found to be higher than that of the films on glass substrates. The estimation of in-plane uniaxial anisotropy was obtained from the hysteresis loops of the films confirmed the experimental in-plane magnetic anisotropy findings. Observations indicate that the uniaxial in-plane magnetic anisotropy and coercivity are dependent on the type of substrate and their rotation speeds.