Observation of room temperature ferromagnetism with giant magnetic moment based on Zn1−xCrxO thin films grown on Si(111) substrate via 1,2-dihydroxyethane modified sol-gel dip-coating technique

Abstract

Dilute magnetic semiconductors have shown a great encouragement from the technological point of view owing to their potential application in multiple spintronics, such as spin light-emitting diode, spin-valve transistor, logic device, nonvolatile memory and ultrafast optical switches. Here, we report on the synthesis of Zn1−xCrxO (0.01≤x≤0.09) thin films grown on Si (111) substrate via 1,2-dihydroxyethane modified sol-gel dip-coating technique for spintronic applications. The influence of partial substitution of Cr ions into the Zn sites on the chemical composition, morphology, crystal structure, and magnetic properties of the prepared films was investigated by the X-ray diffraction (XRD), atomic force microscopy (AFM), high resolution transmission electron microscopy (HR-TEM), dispersive X-ray spectroscopy (EDS), electron diffraction (SAED), X-ray electron spectroscopy (XPS) and vibrating magnetometer (VSM). A single phase and highly crystalline films are obtained. These films showed room temperature ferromagnetism at all Cr ions concentration. The Zn0.95Cr0.05O film showed a remarkable giant magnetic moment of 2.17μB at room temperature. This is the highest magnetic moment value ever achieved among all derived transition elements doped ZnO based dilute magnetic semiconductors till the date.