Magnetic properties and thermal stability of nanocrystalline Fe films prepared by oblique sputtering deposition method

摘要

In this work, nanocrystalline Fe thin films on a Si (100) substrate were successfully prepared using the obliqueangle sputtering technique coupled with applying an external magnetic field of 200 Oe. The crystalline structure, the static magnetic properties, and the high-frequency magnetic characteristics of the as-deposited film were examined using the X-ray diffraction, the M-H loop tracer and the network analyzer, respectively. The results indicate that the nanocrystalline BCC phase of Fe with the average crystallite size of 9.4-11.3 nm and (110) preferred orientation is formed during the deposition process. The difference between M-H loops measured along easy and hard axes confirms the existence of a high in-plane uniaxial magnetic anisotropy which increases with increasing the incident angle. As a result, the ferromagnetic resonance frequency is shifted from 1.02 to 1.88 GHz with an increase of the oblique angle from 0 to 45 degrees. In addition, the film deposited at the oblique angle of 45 degrees, indicates good thermal stability with the maximum imaginary permeability of 513 at 420 K.