Magnetic Properties of Semiconducting Spinel CdCr₂S₄ Nanostructured Films Grown by Low-Pressure Metal–Organic Chemical Vapor Deposition

Abstract

Magnetic semiconductors are being extensively investigated because of their promise to provide new functionalities and device concepts for spintronic applications. Nevertheless, it remains a challenge to obtain high-quality thin films of these materials for device usage, particularly of chalcogenide-based magnetic semiconductors. The chalcogenide spinel CdCr2S4 is a well-established ferromagnetic semiconductor. In bulk form, it exhibits unique properties such as colossal magnetocapacitance and magnetoresistance effects and is a promising candidate for spintronic applications. Because of its semiconducting properties and band gap in the visible wavelength range, CdCr2S4 offers exciting possibilities for tailoring its optical and magnetic properties. However, applications that utilize its unique combination of optical, electrical, and magnetic properties are limited because of difficulties in growing high-quality films. Herein, we demonstrate a simple low-pressure metal–organic chemical vapor deposition (MOCVD) method for growth of high-quality nanostructured CdCr2S4 thin films using metal–organic precursors of Cd and Cr, which provides an attractive route for scaling to large areas. The deposited films are uniform with excellent phase purity, morphology, and crystallinity. In addition to structural and optical characterization, the static and dynamic magnetic properties of the MOCVD grown films have been investigated in detail.