Investigation of Optical and Diode Parameters of 9-[(5-Nitropyridin-2-Aminoethyl) Iminiomethyl]-Anthracene Thin Film

Abstract

The optical, structural and electrical behavior of thin films has been a highly important topic in scientific works and technological applications for many years. Because of this importance, the characteristic behaviors of the film forms are continuously investigated by producing different materials. The goal of the present study is to address in detail the evaluation of the optical properties of 9-[(5-nitropyridin-2-aminoethyl) iminiomethyl]-anthracene (NAMA) organic material and also its use in diode application. For that, the NAMA material known as an organic semiconductor has been synthesized from the reaction between 2-(2-aminoethylamino)-5-nitropyridine and 9-antracene carboxaldehyde under mild reaction conditions. Then, the material dissolved in an organic solvent was grown in thin film form using drop casting on soda-lime glass substrate. Furthermore, the transmittance and reflectance spectra of the grown film were measured in the wavelengths ranging from 200 nm to 2400 nm. The fundamental optical constants such as absorption coefficient ( $$ \alpha $$ ), optical band energy gap ( $$ E_{\text{g}} $$ ), refractive index ( $$ n $$ ) and the dielectric parameters of the thin film were calculated from the optical spectrum values obtained. The optical band gap energy of the film was found as 2.72 eV from standard optical analysis. However, the dispersion parameters were determined in regard to the Wemple-DiDomenico single oscillator model, and the dispersion energy ( $$ E_{\text{d}} $$ ) and the single oscillator energy ( $$ E_{0} $$ ) were found as 14.12 eV and 6.80 eV, respectively. In addition, the Au/NAMA/n-Si/In Schottky diode to determine the electrical parameters was fabricated and the values of ideality factor and barrier height of the fabricated device were obtained as 2.61 eV and 0.724 eV, respectively.