Synthesis and magnetic properties of Cr doped ZnO films via radio frequency plasma deposition

A series of Cr doped ZnO thin films were synthesized by simple radio frequency (RF) plasma deposition. The synthesized films exhibited wurtzite structure with the c-axis normal to the substrate surface. Magnetic measurements indicate that the films are ferromagnetic at room temperature. The deficiency of oxygen content in our samples does allow possible defect mediated mechanisms (e.g., bound magnetic polarons) for mediating exchange coupling of the dopant Cr ions resulting in room temperature ferromagnetism.

► High-quality Cr doped ZnO thin films were synthesized by simple plasma deposition.
► Compared with other ZnO films doped with transitional metals, Zn1−xCrxO films exhibit higher saturation magnetic moment.
► The ferromagnetism of Zn1−xCrxO films is proved to be intrinsic to the Cr–ZnO matrix.
► Experimental results support that the bound magnetic polarons model is legitimate in our samples.