Research Information System
Thesis Type: Postgraduate
Institution Of The Thesis: Gazi University, Fen Bilimleri Enstitüsü, Turkey
Approval Date: 2022
Thesis Language: Turkish
Student: Bahriye ÖZKARA
Supervisor: SEMA BİLGE OCAK, Sema Bilge Ocak
Abstract:
Radiation sensing and radiation sensitive material investigations are very popular among researchers in recent years. In this thesis, the electrical properties of polymer and oxide interfacial layers under ionizing radiation was investigated. Polymer was added between the Al layer and the P-type silicon substrate by using the Lead Oxide (PbO) structure as the oxide interface and Polymethyl Methacrylate (PMMA) the rotational coating method with thermal evaporation method. The obtained MIS structures were exposed to 60Co gamma rays at room temperature, and the differences in the structure before and after the irradiation were investigated. Using the thermal evaporation method on Al/PMMA/ PbO/p(100)-Si structure, ohmic and rectifying contacts are formed and current-voltage (I-V), capacitancevoltage (C-V) and conductance-voltage (G-V) values were measured. The electrical characteristics of the Al/PMMA/PbO/p-Si sample were calculated by using the Thermionic Emission, Cheung and Norde method. Direct and reverse voltage, voltage and the ideality factor (n) of the structure, series resistance value (Rs) and barrier height value (Φb) were calculated by using I-V measurements. 60Co gamma (γ) radiation increased the Rs and Φb on the Al/PMMA/PbO/p-Si structure. On the other hand, it had a decreasing effect on the ideality factor. Thus, it was understood that the structures with the polymer and oxide interface layer were sensitive to 60Co gamma (γ) radiation. Consequently, it can be inferred from experiment that structures with the polymer and oxide interface layer are sensitive to 60Co gamma (γ) radiation. In addition, electrical charecteristics of Al/PMMA/PbO/p(100)- Si calculated by using 100 kHz, 300 kHz, 500 kHz, 700 kHz, 800 kHz and 1 MHz frequencies at room temparature before and after 60Co gamma (γ) rays show that this structure was sensitive to 60Co gamma (γ) rays and the structure could be used as a radiation sensor.
| Key Words : Electrical characteristic, Gamma-ray irradiation, PbO, PMMA |