Effect of Vacuum Annealing on the Optoelectric and Morphological Properties of F₁₆CuPc Thin Films

Abstract

The effect of vacuum annealing temperature on optical and electrical properties of vacuum evaporated F₁₆CuPc thin films have been studied spectrophotometer and Kiethely electrometer respectively. The band gap energy both fundamental and excitonic remains unchanged when the annealing temperature increased. The optical constants of thin films are obtained by means of thin film spectrophotometry. From the electrical study, the activation energies of the films, in the intrinsic region and impurity region have been determined from the Arrhenious plots of lnσ versus 1000/T. Optical data have been obtained from both absorption and reflectivity spectra over the wavelength range 200-800 nm. The absorption coefficient α and extinction coefficient k are estimated from the spectrum. The mechanism of optical absorption follows the rule of direct transition. Using α and k, the refractive index and the dielectric constants are determined. The SEM investigations are F₁₆CuPc thin films are expected to find application in the fabrication of optoelectronic devices such as organic transistors and LED devices.