Analysis and characterization of silicon clusters embedded in ZnO amorphous matrix grown by magnetron co-sputtering at room temperature

Abstract Amorphous ZnO/Si (a-ZnO/Si) precursor films were produced to promote the formation of Si clusters within an amorphous ZnO matrix. The Si nanoclusters were induced into the ZnO/Si nanocomposite films through a spinodal decomposition, facilitated by post-growth annealing in a N 2 atmosphere at low temperatures. The a-ZnO/Si nanocomposite films were deposited by co-sputtering at room temperature, achieving a thickness of approximately 120 nm. Sputtering was performed in an ultra-high purity (UHP) argon atmosphere, and the films were characterized both structural and optically. The precursor nanofilms, with a Si atomic content of 12% as determined by EDS analysis, were electrically insulating. Post grown annealing at 500 °C for 5 min led to the formation of Si clusters with sizes running up to of 20 nm. Measurements of the refractive index, photoluminescence, XRD patterns confirmed the presence of Si clusters within the amorphous ZnO matrix. Graphical abstract