Research Information System
Thesis Type: Postgraduate
Institution Of The Thesis: Gazi Üniversitesi, Fen Bilimleri Enstitüsü, Turkey
Approval Date: 2019
Student: GÖKÇER GÜNEŞ
Supervisor: SEMA BİLGE OCAK
Abstract:We have investigated the effects of 60Co gamma-ray irradiation on the electrical properties the composite structure of the poly (methyl methacrylate) /leadoxide nanoparticle (PMMA/PbO). For this purpose, PbO interface layer was coated on a p-type silicon substrate by thermal evaporation technique and PMMA organic structure has grown on oxide/ p-type silicon substrate as a thin film by using spin coating method to form metal /oxide/organic structures. After formation of ohmic and rectifier contacts by thermal evaporation technique the voltage dependent current measurements of structures have been performed at room temperature and in a dark environment. By means of obtained data from the measurements the basic diode parameters have been examined using different techniques. After characterization process, the structures have been exposed to gamma rays of 30 kGy using a 60Co gamma source and the characterization process have been repeated in order to examine the changes of basic parameters after radiation. In order to explore the γ-ray effect on electrical parameters of metal /oxide/organic structures Standart and Cheung methods have been used. The voltage dependent current curves of structure have been showed a Schottky type behaviour before and after radiation. While ideality factor has decreased, series resistance has increased after ionized radiation. This case has been attributed to the series resistance effect and formation of acceptor-like interface states generated by radiation.