Ferromagnetic Cu and Al doped ZnO thin films by PLD

Abstract

The present study is focused on the detailed characterization of (ZnO) 1-x(CuO)x(Al2O3)0.002 bulk samples and their thin films. XRD of bulk samples showed ZnO peaks without impurity phase which indicates maximum substitution of copper inside the ZnO lattice. Raman spectra showed a random shift of modes which might be due to point defects created by copper and aluminium substitution in ZnO. VSM showed weak ferromagnetic behavior in samples indicating Cu ion substitution in ZnO. XPS further confirmed the presence of Cu+2 states in the bulk samples. After detailed characterization of bulk samples, these samples were utilized as targets for deposition of thin films using PLD technique. Highly crystalline films of doped ZnO with (002) orientation were grown on (100) Si substrates. Compositional analysis of thin films done by XPS showed the presence of Cu+2 ions which is the source of ferromagnetism in our thin film samples. M-H curves showed the ferromagnetic behavior for the films. Thin films are magnetic and conductive at room temperature. © 2010 IOP Publishing Ltd.