Magnetic properties of iron nitride films prepared by oblique sputtering under different nitrogen gas flow ratios (N2/N2+Ar)

Iron nitride thin films were prepared on Si (100) substrates by oblique radio-frequency reactive magnetron oblique sputtering. Structures, phases and magnetic properties were investigated as a function of nitrogen gas flow ratio F-N(F-N=F-N2/(F-N2 +F-Ar) x 100%). When FN is in the range of 2-7%, the iron nitride films show amorphous or nano-crystalline structures, which exhibit good soft magnetic properties. With 3% <= F-N <= 6%, films show in-plane uniaxial magnetic anisotropy. Both intrinsic damping factor alpha(in) and extrinsic damping factor alpha(ex) of the iron nitride films increase with increasing F-N. The film deposited under F-N=6% with the resonance frequency f(r)=3.3 GHz and full width at half-maximum Delta f=3.6 GHz has great potential for high-frequency electromagnetic shielding applications. (C) 2015 Elsevier Ltd. All rights reserved.