Growth and topography study of MnBi films

We deposited (Mn/Bi)x bilayers (x=1,2,3) on clean glass substrates at room temperature and at 200 °C without using a protective SiOx layer in order to investigate the interaction between preparation conditions, homogeneity, granularity, and topography. During annealing at temperatures between 280 and 320 °C, no protective SiOx layer on top of the (Mn/Bi)x bilayers influences the formation of MnBi crystallites, i.e., the granularity. The coercive field of the resulting MnBi films is enhanced reaching values of up to 1.25 T. The large coercive fields indicate a single-domain MnBi crystallite size of only 0.2–0.3 μm, which is favorable for a possible application as a magneto-optic storage material.