Broadband strip-line ferromagnetic resonance spectroscopy of soft magnetic CoFeTaZr patterned thin films

• Main Authors: S. Gupta, D. Kumar, T. L. Jin, R. Nongjai, K. Asokan, A. Ghosh, M. Aparnadevi, P. Suri, S. N. Piramanayagam
• Format: Article
• Language: English
• Published: AIP Publishing LLC 2018-05-01
• Series: AIP Advances
• Online Access: http://dx.doi.org/10.1063/1.5007943

In this paper, magnetic and magnetization dynamic properties of compositionally patterned Co46Fe40Ta9Zr5 thin films are investigated. A combination of self-assembly and ion-implantation was employed to locally alter the composition of Co46Fe40Ta9Zr5 thin film in a periodic manner. 20 keV O+ and 60 keV N+ ions were implanted at different doses in order to modify the magnetization dynamic properties of the samples in a controlled fashion. Magnetic hysteresis loop measurements revealed significant changes in the coercivity for higher influences of 5 × 1016 ions per cm2. In particular, N+ implantation was observed to induce two phase formation with high and low coercivities. Broadband strip-line ferromagnetic resonance spectroscopy over wide range of frequency (8 – 20 GHz) was used to study the magnetization dynamics as a function of ion-beam dosage. With higher fluences, damping constant showed a continuous increase from 0.0103 to 0.0430. Such control of magnetic properties at nano-scale using this method is believed to be useful for spintronics and microwave device applications.