Optical parameters extraction of zinc oxide thin films doped with manganese using an innovative technique based on the dragonfly algorithm and their correlation to the structural properties

Abstract

Pure zinc oxide (ZnO) thin films, along with manganese (Mn) doped counterparts, were produced using rapid thermal evaporation technique on ordinary glass substrates. Postannealing treatments resulted in the formation of hexagonal wurtzite structures in the deposited layers. The Raman results unveiled the presence of A1(LO) and LVM vibration modes in each sample that were doped. Interestingly, the undoped sample lacked the LVM mode while showcasing the emergence of LA + TO combined phonons. Employing a novel approach reliant on the Dragonfly Algorithm, optical parameters were extracted, revealing a drop in the bandgap energy of the films from 3.95 eV to 3.79 eV.