Structural, morphology and optical properties of Zn(1-x)CdxO solid solution grown on c-plane sapphire substrate

Abstract

Zn(1-x)CdxO solid solutions with a composition ranging from pure ZnO up to x=0.046 have been grown on cplane sapphire substrates by using metal organic chemical vapor deposition (MO-CVD). The lattice deformation, morphology and optical properties of these films were examined in detail using high resolution X-ray diffraction, atomic force microscopy (AFM) and photoluminescence (PL) as Cd incorporation. Our study reveals significant microstructure modification of Zn(1-x)CdxO from x≥0.7% but single phase of wurtzite structure is maintained for all films. The Pl spectra and the band gap of the Zn(1-x)CdxO film show red shift to visible light range which is interpreted in terms of band gap modulation due to Cd incorporation. Increase of Cd content leads to the emission broadening with growing lower energy peak (at 10K) and degraded crystallinity.