The influence of hydrogen annealing on the morphology, microstructure and magnetic properties of CoPt films was investigated. After changing the annealing environment from vacuum to hydrogen, the coercivity of the CoPt films increased from 610 to 2100Oe at 500C. The more complete phase transformation may be attributed to the dissolution of hydrogen atoms in the interstitial sites of the CoPt lattice. Moreover, the size of the CoPt grains was smaller and the distribution was much more uniform in the hydrogen-annealed samples. The morphology change may be due to the existence of hydrogen atoms in the CoPt grain boundary which can inhibit the growth and coalescence of the CoPt grains.

Effect of Hydrogen Annealing on L10 Ordering Transformation and Magnetic Properties of CoPt Thin Films on B4C Underlayer. F.Yang, H.Wang, H.Wang, J.Zhang, J.Zhu, Q.Li, Y.Jiang: Journal of Physics D, 2009, 42[11], 115001