Postgraduate Student from the Medical and Industrial Materials Science Branch Earns a Master’s Degree
The Department of Biomedical and Industrial Materials Science awarded a Master’s degree to graduate student Mustafa Abdul Sahib Najm for his thesis titled:
“Effect of Seed Layer Type on Copper Oxide Thin Films Prepared by Chemical Bath Deposition”
The defence took place in the department building of the late Professor Dr. Abdul-Muttalib Ibrahim Al-Sheikh Hall.
In this study, seed layers for copper oxide were prepared using three different precursor materials, and seed layers of iron(III) oxide (hematite) and nickel oxide were prepared using the thermal chemical spray technique. These seed layers served as substrates for the subsequent deposition of copper oxide thin films using the chemical bath deposition (CBD) method, where ammonium hydroxide was used as a complexing agent. The films were annealed at 400°C after deposition. The structural properties (X-ray diffraction (XRD), field emission scanning electron microscopy (FESEM), and energy-dispersive X-ray spectroscopy (EDS)), optical properties (UV-Vis spectroscopy), and electrical properties (DC conductivity, Hall effect, and current-voltage (I-V) characteristics) of the copper oxide thin films were investigated to assess the effect of seed layers on enhancing their efficiency in optoelectronic applications. X-ray diffraction (XRD) tests revealed that the copper oxide thin films exhibited a monoclinic crystal structure, varying the preferred growth orientations. FESEM images showed that the morphology of the copper oxide thin films was influenced by the type of seed layer, affecting the uniformity and aggregation of grains. A smoother surface of the seed layers, as indicated by FESEM analysis, resulted in the appearance of a more significant number of diffraction peaks in XRD analysis for the subsequently deposited films. EDS analysis confirmed the absence of impurities in the copper oxide films, and elemental mapping demonstrated a homogeneous distribution of copper and oxygen atoms, with the most uniform distribution observed in films deposited on copper oxide seed layers. UV-Vis spectroscopy analysis indicated that the prepared films had an energy band gap ranging from 1.47 to 1.65 eV, determined using Tauc’s plot. Furthermore, Urbach energy decreased in the presence of seed layers, with the most significant reduction observed in films deposited on copper oxide seed layers. DC conductivity measurements revealed variations in activation energy (0.192–0.532 eV) and electrical conductivity values, which ranged from (6.24×10⁻⁶ – 2.30×10⁻² S·cm⁻¹) depending on the type of seed layer. A direct correlation was observed between the number of diffraction peaks in XRD analysis and electrical conductivity. Hall effect measurements showed that copper oxide thin films deposited on seed layers exhibited higher carrier mobility than those deposited directly on glass. In both cases, the majority of charge carriers were holes.Additionally, the I-V characteristics of the prepared thin films demonstrated an improved rectifying behaviour in the presence of seed layers. The photoelectrical conductivity of the films was further enhanced by the incorporation of ruthenium dye (N719).
The thesis defense committee was consist of:
- Prof. Dr. Uday Ata Hammadi
Al-Iraqia University / College of Education / Department of Physics – Chairman - Asst. Prof. Dr. Mufeed Abdul Latif Jalil
Department of Applied Sciences / Biomedical and Industrial Materials Science Branch – Member - Lecturer Dr. Manal Abdul Wahid Aboud
Department of Applied Sciences / Biomedical and Industrial Materials Science Branch – Member - Asst. Prof. Dr. Mustafa Amer Hassan
Department of Applied Sciences / Biomedical and Industrial Materials Science Branch – Member and Supervisor - Prof. Dr. Khalil Ibrahim Hassoun
Department of Applied Sciences / Laser Science and Technology Branch – Member and Supervisor
