Local study of the magnetism of Co-doped ZnO thin films

摘要

Complementary electron microscopy techniques that provide local information about structural, electronic and magnetic properties have been used to study thin films of Zn0.85Co0.15O grown on Si3N4 buffered (100) Si substrates at 673 K. No evidence of secondary phases at interfaces was found. For this growth temperature, Co is incorporated into the ZnO lattice by substituting for Zn, and its oxidation state is 2(+). Off-axis electron holography reveals no measurable magnetic signal, either at domains or at interfaces, in agreement with macroscopic measurements that indicate a non-ferromagnetic behaviour.