Epitaxial Growth of Ni-Fe/Mn-Ni Bilayers on MgO Single-Crystal Substrates by the Facing-Targets Sputtering Method

摘要

Ni-Fe/Mn-Ni bilayers were fabricated at roomtemperature on MgO{100} and MgO{110} single-crystalsubstrates by the facing-targets dc sputtering method. The Ni-Felayer was deposited by applying a bias voltage. After thedeposition of the Ni-Fe layer, an Mn-Ni layer was deposited onthe Ni-Fe layer. The Ni-Fe and #gamma#-Mn-Ni layers weregrown by epitaxy and highly oriented in their crystal axes in thefilm plane. In the case of the MgO{100} substrate, the preferredorientations of Ni-Fe and #gamma#-Mn-Ni were (001), and thedirections of Ni-Fe(100) and #gamma#-Mn-Ni(100) wereparallel to MgO(100). The crystal structure of #gamma#-Mn-Niwas fct, and c/a decreased from 1.01 to 0.984 when the Mn-Nilayer thickness increased from 200 to 1000 ?. In the case of theMgO{110} substrate, the preferred orientations of Ni-Fe and#gamma#-Mn-Ni were (110), and the directions of Ni-Fe (001)and #gamma#-Mn-Ni(001) were parallel to the direction ofMgO(001). The crystal structure of #gamma#-Mn-Ni was fct (c/a = 0.978).