Akademik Veri Yönetim Sistemi
PHYSICA B-CONDENSED MATTER, cilt.704, 2025 (SCI-Expanded)
In this study, zinc oxide (ZnO) thin films with 15 % iron (Fe) doping (Zn0.85Fe0.15O) were synthesized on glass and p-type silicon (Si) substrates via sol-gel dip coating and spraying methods. Structural characterization was performed using scanning electron microscopy (SEM), energy dispersive spectroscopy (EDS), and X-ray diffraction (XRD), all of which confirmed the formation of pure Fe-doped ZnO nanoparticles with a hexagonal ZnO polycrystalline structure. The optical transmittance in the visible spectrum was approximately 90 %, and the band gap energy, determined using the Tauc method, was 3.23 eV. The refractive index of the sample decreased from 1.8 to 1.5 as the wavelength increased in the visible spectrum. Photoluminescence (PL) analysis revealed a band gap energy of 3.27 eV, with emissions at 2.45 eV and 1.81 eV. These last two emissions were attributed to transitions from the conduction band to zinc vacancies and oxygen interstitial defect levels, respectively. The electrical properties of the 15 % Fe-doped ZnO thin film on the Si substrate with gold (Au) contacts were evaluated using current-voltage (I-V), Cheung, and Norde methods. The measurements yielded an ideality factor between 3.78 and 5.7, a barrier height ranging from 0.57 eV to 0.66 eV, and series resistance values between 19.3 k Omega and 49.1 k Omega. Notably, as temperature increased, the Seebeck coefficient and electrical conductivity improved, while thermal conductivity decreased. The thermoelectric material achieved maximum efficiency of 0.004 at 550 K, with a Seebeck coefficient of around -2000 mu V/K.