Extended defect structures in zinc oxide doped with iron and indium

Abstract

The effects of iron- and indium oxide doping on the structure and magnetic susceptibility of ZnO have been studied. The nominal compositions were In _x Fe _2–x O ₃ (ZnO) _n with 0≤x≤1 and n=23, 48 and 98. Magnetic measurements showed the iron-doped samples to be paramagnetic, with a behaviour indicating antiferromagnetic coupling between the iron ions. HREM studies showed that indium and iron are incorporated as layer defects of two kinds. One type forms cubic close packed (ccp) planes perpendicular to the c axis, and the other appears as corrugated layers inserted between the former. The folds in the corrugated layers consist of alternating (114) and (11) planes. Analytical transmission electron microscopy studies revealed that indium prefers the ccp layers, whereas iron can be found in both types of defects. Structural models based upon the experimental results are presented.