Magnetoresistance and preferred orientation in Fe-Mn/Ni-Fe/Cu/Ni-Fe sandwiches with various buffer layer materials

Magnetoresistance effects and film structures have been investigated in [Fe–Mn/Ni–Fe/Cu/Ni–Fe/buffer layer/Si] sandwiches with various buffer layer materials. The sandwich with Nb, Ta, Ti, Zr or Hf buffer layer has strong (111) texture. Cu, Ag, Au and Cr buffer layers do not cause strong (111) texture. When the sandwich has strong (111) texture, the Ni–Fe layer neighboring the Fe–Mn antiferromagnetic layer is strongly exchange-biased by the Fe–Mn layer, and thus the sandwich shows a high magnetoresistance ratio.