Abstract
In this study, Erbium tris-8-hydroxyquinoline (Erq(3)) thin films were deposited on a cleaned glass substrate using the thermal evaporation technique and then thermally annealed up to 523 K. The morphology, optical and electrical properties were investigated for as-deposited and annealed thin films. The grain sizes observed by AFM of the Erq(3) thin films vary between 80 and 130 nm. The average surface roughness of the Erq(3) thin films was seen to range between 46 and 65 nm. The increase in the annealing temperatures leads to an increase in the average crystallite size by about 60%. The evolution of the electrical and optical properties of our prepared thin films due to the annealing process was correlated with their structural properties. According to Tauc's theory, a slight increase in the energy gap by about 0.17 eV due to the annealing process was recorded. The nonlinear parameters of Erq(3) such as chi 3 and n(2) decreased by about 41% and 45% due to the increase of the annealing temperature up to 523 K. The increase of the annealing temperature up to 523 K leads to the decrease of the nonlinear coefficients of Erq(3) due to the decrease of the localized defect states.