Growth and Magnetic Characterization of High Manganese Silicide Thin Films

Abstract

Manganese silicide thin films have been successfully deposited by dc magnetron sputtering with Mn concentrations up to the high manganese silicide (HMS) range near MnSi1.7. We observed the formation of a number of tetragonal crystallite phases, including Mn4Si7, Mn27Si47, and Mn15Si26, which are commonly referred to in the literature as near MnSi1.7 or HMS; all of these phases have been confirmed using X-ray Diffraction. The formation of more HMS phases begin to appear at Mn concentrations around 29%, with XRD patterns clearly exhibiting the formation of the HMS phases with increased Mn concentrations. The low temperature saturation magnetization of these films increases with increased Mn concentration with a peak value of 100emu/cc for films near the MnSi1.7 range. Films are paramagnetic at room temperature but start to exhibit ferromagnetism at low temperatures with the Mn concentrations around 35%, which corresponds to the MnSi1.7 phases. Films close to MnSi1.7 have a coercivity of about 300 Oe.