Characterization of organic thin film devices for direct X-ray photoconversion

The main purpose of this thesis is to present the fundamental characteristics of organic thin film devices for direct X-ray photoconversion. In the first part of this study will be presented the theoretical background of X-rays, X-rays detection and the theory organic devices. In the second part will be considered in details the process of fabrication and characterization of organic devices projected for X-rays detection. The subjects of this thesis are some samples realized at the laboratories of the Department of Physics and Astronomy of Bologna: their fabrication and their electrical and X-rays characterization will be analised in this work. These samples have been realized on 5 different ”substrates” in order to study their effect on the behaviour of the device. In the third and last part will be presented the characterization of a TIPGe device realized at the labora- tories of the Department of Physics and Astronomy of Bologna, and tested at Skan-X Radiology Devices S.p.A. The collaboration with this company offered the possibility to test the device with a complete different sets of parameters, in energy and dose range typical of dental medical applications. Moreover it was a constructive collaboration under the aspect of further developments of the device: physicists and experts from Skan-X Radiology Devices S.p.A. and from SkanRay S.p.A. defined the key points that organic thin film devices for direct X-ray photoconversion should have to work as a X-rays detectors for radiographic imaging. The encouraging results placed the bases for further analysis such as testing the device with other X-ray machine or/and trying to better understand the effect of the substrates on the behaviour of the device. In addition they represent the starting point for the beginning of the process of scaling of the device in order to move towards the fabrication of a prototype of X-rays detector for radiographic imaging