Applied Sciences Dept. Discusses A Master Thesis of  the Student/ Dhuha Shaker Hassan

A master thesis has been discussed in Applied Sciences Dept. at U.O.T. entitled:

( Studying The Effects of OTA and Ar Gas Annealing Technique on The Physical Properties of ZnO Thin Film Prepared by PLD) 

An MSc. Thesis has been discussed for Dhuha Shaker Hassan, major in laser science and technology, included the deposition of zinc oxide films on glass bases using Pulsed Laser Deposition (PLD) technology, with a laser intensity (35.4 J/cm2) with a focus of 10 cm using a ND_YAG Laser  with a wavelength of 1064 nm, 150 number of pulses in At room temperature under a vacuum of up to millibar, then after the sedimentation process, a thermal treatment (annealing) of these films was carried out using the thermal annealing technique with oil (OTA) and annealing using argon gas (Ar)    at temperatures (150◦ C, 200◦ C, 250◦ C, 300◦ C) for 10&20 minutes of time. 

Her study showed the effect of thermal annealing on the structural, optical and electrical properties of zinc oxide (ZnO) films using an X-ray diffraction device to study the crystallization of the films. The particle size of the films is 17.6 nm before annealing and increases after annealing from 19.5 nm to 25.4 nm when annealed with argon (Ar) gas, with an increase of more than 19.8 nm to 26.2 nm when annealed with oil with increasing temperatures from 150 Celsius to 300 Celsius, respectively.

To study the topography of the surface of the film, an atomic force microscope is used, where it was found that the surface roughness of the zinc oxide film is 75 nm before annealing, and the surface becomes smoother, as the roughness decreases to as low as 46 nm when annealing with oil at a temperature of 300 degrees Celsius. The improvement of the film permeability was observed from 74.1% to 94% in the visible spectrum region after annealing with oil at a temperature of 300 Celsius by using a (UV_VIS) device to study the permeability and absorption spectra of the films. 

 The change in the energy gap occurs, where a decrease is observed from 332.3 to 3.250 electron volts after annealing with oil at a temperature of 300 Celsius. The measurement of the effect of Hall on the films was carried out in order to know the electrical parameters, as it shows that the concentration of charge carriers is 5.65 x 1019 (cm-3) and it increases after annealing to 2.97 x 1020 (cm-3) and 3.92 x 1020 (cm-3), and the resistance Before annealing it is 5.45 x 10-3 (Ω cm) and decreases to 2.97 x 10-3 (Ω cm) and 1.98 x 10-3 (Ω cm) after annealing with argon gas and oil at 300 °C, respectively.

The discussion committee consisted of:

1- Prof.  Dr. Khawla Salah Khashan / Chairman.

2-  Asst. Prof. Dr. Fatima Arees Sultan / Member.

3- Asst. Prof. Dr. Layla A. Wali / Member.

4-  Asst. Prof. Dr. Qasim Zayer Mahdi / Supervisor.