The effects of annealing temperature on the structural properties and optical constants of a novel DPEA-MR-Zn organic crystalline semiconductor nanostructure thin films

The dependence of structural properties and optical constants on annealing temperature of a 2-((1,2-bis (diphenylphosphino)ethyl)amino) acetic acid-methyl red-monochloro zinc dihydride (DPEA-MR-Zn) as a novel organic semiconductor thin film was studied. The DPEA-MR-Zn thin film was deposited on silicon substrates using the spin coating technique. The as-deposited film was annealed in air for 1 h at 150, 175 and 205 degrees C. The XRD study of DPEA-MR-Zn in its powder form showed that this complex is mere a triclinic crystal structure with a space group P-1. In addition, the XRD patterns showed that the as deposited thin films were crystallized according to the preferential orientation [(214), (121), (0 (2) over bar6), ((3) over bar 02), (122) and (11 (4) over bar)]. Moreover, two additional peaks ((22) over bar1 and 2 (4) over bar7) were shown at 2 theta nearly 30 degrees, and 69 degrees, where, the more annealing temperature, the more the intensity of the two peaks. In addition, it was noticed that the grain size had a remarkable change with an annealing temperature of the DPEA-MR-Zn thin films. The optical measurements showed that the thin film has a relatively high absorption region where the photon energy ranges from 2 to 3.25 eV. Both of Wemple-DiDomenico and single Sellmeier oscillator models were applied on the DPEA-MR-Zn to analyze the dispersion of the refractive index and the optical and dielectric constants. The outcome of the study of the structural and optical properties reported here of the DPEA-MR-Zn organic semiconductor crystalline nanostructure thin film had shown various applications in many advanced technologies such as photovoltaic solar cells. (C) 2017 Elsevier B.V. All rights reserved.