Spectroscopic ellipsometry studies on ZnCdO thin films with different Cd concentrations grown by pulsed laser deposition

摘要

Graphical abstract Display Omitted Highlights • The variable angle ellipsometry data were measured for Zn1-xCdxO (x=0.05,0.10). • VASE shows a red shift in the absorption edge with increasing Cd contents. • Temperature-dependent spectroscopic ellipsometry were studied from 25°C to 600°C. • Have obtained the optical constants and band gaps of Zn0.95Cd0.05O film by TDSE. Abstract A set of Zn1-xCdxO thin films with different Cd concentrations was deposited on quartz substrates by Pulsed Laser Deposition (PLD). The properties of these films were investigated by variable angle and temperature dependent spectroscopic ellipsometry (SE). The experimental Zn1-xCdxO thin films showed a red shift in the absorption edge with increasing Cd contents at room temperature. For ZnCdO films with the similar Cd concentration, it has been found that the film thickness has important effects on the optical constants (n, k). The variations of optical constants (n, k) and the band gap, E0, with temperature (T) in 25°C–600°C for a typical Zn0.95Cd0.05O sample were obtained. The E0 vs T relationship is described by a T- quadratic equation.