STUDENT ACADEMIC ACHIEVEMENT
MECHANISMS AND DEVELOPMENT PROPERTIES THIN FILMS
Mr. Christos Koidis, PhD candidate of A.U.Th, was awarded with the young scientist award in a Symposium of European Materials Research Society 2010, in Strasbourg, for his research, which refers to the study of the development mechanisms, of opto-electronics and nanomechanical properties of Al-doped ZnO thin films that were developed with the Magnetron Sputtering and E-Beam Evaporation techniques.
This project is a part of his PhD thesis, in the context of which a study of materials and processes took place for the manufacture of integrated Organic Electronic devices (OH), such as Flexible Organic Photovoltaics (OPVs) in order to increase efficiency and reduce costs through the adoption of mass production processes, such as Roll-to-Roll printing, and the use of alternative indium tin oxide materials. In parallel, the fabrication of functional OPVs by printing processes has taken place, demonstrating the potential for the production of useful OH in a variety of applications such as energy, lightning, electronics, etc.
Development and study of alternative conductive materials in order to replace the transparent conductive indium tin oxide
ZINC OXIDE THIN FILMS
The thin films based on zinc oxide (ZnO) are one of the most promising candidates as transparent conductive oxides in optoelectronic devices, replacing the expensive indium tin oxide (ITO). In particular, Al-doped zinc oxide thin films (AZO) lead to the improvement of the optical and electronic properties of ZnO.
In this study the growth mechanisms have been investigated as well as the optical, structural, electrical, and Nanomechanics properties of the films which were developed with the Magnetron Sputtering and Electron Beam Evaporation techniques (electron beam sublimation) under different conditions such as different strengths to the target (Pt) and different substrate temperature (T). Also, rigid substrates were used such as crystalline silicon (c-Si) and glass as well as flexible substrates like poly(ethylene terephthalate) (PET).
For the characterization of the films the Spectroscopic Ellipsometry technique was used in the visible-ultraviolet long (1.5-6.5 eV), receiving spectra in real time during development. For Pt = 135 W AZO films development made in layers while Pt> 200 W in islets. The X-ray diffraction and Transmission Electron Microscopy (TEM) revealed an increase in the nanocrystals size with increasing T, while with the Atomic Force Microscopy (AFM), reduced surface roughness was observed. A correlation of all results was carried out in order to understand the mechanisms that determine the properties of thin films AZO.
European Materials Research Society, 2010
The award from the E-MRS concerns the research of the PhD candidate Christos Koidis from the School of Physics, A.U.TH, entitled "Study of the development mechanisms of opto-electronics and nanomechanical properties of Al-doped ZnO thin films that were developed with the Magnetron Sputtering and E-Beam Evaporation techniques". The research took place at the Laboratory for Thin Films and Nanosystems Nanometrology (LTFN) under the supervision of professor Stergios Logothetidis. The E-MRS organizes scientific meetings, with around 2,500 participants each year, where the latest technological developments of functional materials are presented, aiming to promote the effective partnerships between industries and research laboratories, as well as cooperation with funding agents.
ARISTOTLE UNIVERSITY OF THESSALONIKI
Christos Koidis, PhD Candidate A.U.TH.
Panagiotis Karagiannidis, PhD Candidate A.U.TH, Spriros Kasavetis, Postdoctoral Researcher A.U.TH,
Argiris Laskarakis, Postdoctoral Researcher A.U.TH.
Head of Research Team: Stergios Logothetidis, Professor of the School of Physics A.U.TH, Scientific Responsible.
Laboratory for Thin Films Nanosystems and Nanometrology - LTFN.http://ltfn.physics.auth.gr