Ferromagnetic metals on II-VI semiconductors: epitaxial growth, and structural and magnetic properties

We have studied the growth conditions to obtain the chemically well ordered L1(0) phase of the FePd alloy deposited on ZnSe and CdZnMgTe II-VI semicon ductors. We have observed that the segregation of Se or Te atoms at the sur face involved a dramatic effect on the formation of the L1(0) phase. The st rong anisotropy exhibited along the growth direction allows to observe, by magnetic force microscopy, the perpendicular magnetic configuration with up and down domains. Comparably, we have grown, on the same materials, Cu/Ni multilayers showing a clear perpendicular magnetic anisotropy. Optical meas urements on a semimagnetic heterostructure covered by a ferromagnetic metal layer suggest fluctuations of the Fermi level at the interface between the semiconductor and the metal. (C) 2001 Elsevier Science B.V. All rights res erved.