Title :
Enhancement of Microwave Properties of FeCoN Films on Mica Substrates by Control of SiO2 Underlayer Thickness
Author :
Yuping Wu ; Yong Yang ; Zhihong Yang ; Baoyu Zong ; Jun Ding
Author_Institution :
Temasek Labs., Nat. Univ. of Singapore, Singapore, Singapore
fDate :
7/7/1905 12:00:00 AM
Abstract :
A thin SiO2 underlayer has been found to be effective to enhance the microwave properties of FeCoN films on mica substrates. In this study, the effect of SiO2 thickness on static and dynamic magnetic properties was studied. A 160 nm FeCoN film directly deposited on a mica substrate exhibited in-plane isotropy, accompanied by a large coercivity of 70 Oe. By inserting a thin SiO2 as the underlayer, the anisotropy and coercivity were dramatically changed. When the thickness of SiO2 was 40nm, the film had well-defined in-plane anisotropy, and the coercivity greatly decreased to less than 3Oe. Correspondingly, excellent microwave properties were obtained with a strong magnetic resonance at 2.8GHz. However, both the static and dynamic magnetic properties declined rapidly with the further increase in the thickness of SiO2, which is related to the large damping effect due to the increased surface roughness and residual stress of the SiO2 layer.
Keywords :
cobalt compounds; coercive force; internal stresses; iron compounds; magnetic anisotropy; magnetic resonance; magnetic thin films; microwave spectra; surface roughness; Al2O3-K2O-SiO2; FeCoN; coercivity; damping; dynamic magnetic properties; frequency 2.8 GHz; in-plane anisotropy; magnetic resonance; mica substrates; microwave properties; residual stress; static magnetic properties; surface roughness; underlayer thickness; Damping; Films; Magnetic properties; Resonant frequency; Substrates; Surface morphology; Surface treatment; Magnetic and spintronic materials; ironcobaltnitride; magnetic anisotropy; magnetic coercivity; mica substrates; microwave materials;
Journal_Title :
Magnetics Letters, IEEE
DOI :
10.1109/LMAG.2015.2462808
