Pulsed laser deposition of sometco films for optoelectronic application
Dissertant
University
University of Technology
Faculty
-
Department
Applied Sciences Department
University Country
Iraq
Degree
Ph.D.
Degree Date
2006
English Abstract
Design and construction of reactive pulsed laser deposition system have been carried out, and used in the preparation of High quality transparent conductive ZnO and Cd O thin films, using (400 use) Nd-YAG laser to the ablation of Zn and Cd targets respectively, on silicon and glass substrates.
Many growth parameters have been considered in this work to specify the optimum conditions, namely, laser energy density, number of shots, oxygen background pressure and substrate temperature.
Optical, electrical and structural properties of ZnO and Cd O films are investigated and analyzed extensively with respect to growth condition.
The optical properties of ZnO films reveal that the optical band gap varied over the range (3-3.15) eV and (2.4-2.7) eV for ZnO and Cd O, respectively depending on reactive gas pressure.
High transparency reached about 85 % of that achieved with ZnO film, which itself decreases sharply with decreasing oxygen pressure.
The electrical properties of undoes ZnO and Cd O films confirm that these films are n-type and highly conductive.
The electrical resistivity of both films is found to be very sensitive to substrate temperature and oxygen pressure.
Lowest resistivity of about (0.0074) Q.cm is found for Cd O film prepared at (350 Torr).
Heterojunction photo detector has been fabricated by depositing both Cd O and ZnO films on monocrystalline (111) p-type silicon substrate at different conditions, the main parameters of ZnO / p-Si, and Cd O / p-Si photo detectors are investigated.
The responsively of the detectors found to be (0.2, 0.22) A / W, while the directivity found (2.13, 3.82) x 10t2 cm.HzI / 2.Wl.
The XRD spectra revealed that the highly oriented grain in the (101) direction for the ZnO film and in the (111) direction for the Cd O film can be obtained with narrow peak at best preparation conditions of (02 pressure = 300 Torr, Tsub = 473K for Zn O) and (02 pressure = 350 Torr, Tsub = 523K for Cd O).
All films grown at these conditions exhibit full stoichiometric type.
Main Subjects
Topics
American Psychological Association (APA)
al-Waisy, Evan T. Salim. (2006). Pulsed laser deposition of sometco films for optoelectronic application. (Doctoral dissertations Theses and Dissertations Master). University of Technology, Iraq
https://search.emarefa.net/detail/BIM-305703
Modern Language Association (MLA)
al-Waisy, Evan T. Salim. Pulsed laser deposition of sometco films for optoelectronic application. (Doctoral dissertations Theses and Dissertations Master). University of Technology. (2006).
https://search.emarefa.net/detail/BIM-305703
American Medical Association (AMA)
al-Waisy, Evan T. Salim. (2006). Pulsed laser deposition of sometco films for optoelectronic application. (Doctoral dissertations Theses and Dissertations Master). University of Technology, Iraq
https://search.emarefa.net/detail/BIM-305703
Language
English
Data Type
Arab Theses
Record ID
BIM-305703
