The 2010 IUVSTA Prize for Science was awarded to Dr. Péter B. Barna “for his outstanding results in understanding thin film growth phenomena and structure- property relations in one and multiphase thin films.”
Dr. Péter B. Barna obtained his PhD in physics from the Hungarian Academy of Sciences (Budapest) in 1967. He became the head of the Thin Film Physics Department of the Research Institute for Technical Physics, Hungarian Academy of Sciences (1961). His scientific career was continued and he became titular Professor at Kossuth University, Debrecen, in 1991. He has defended his Doctor of Sciences thesis at the Hungarian Academy of Sciences in 1999. He is the author and co-author of about 200 scientific papers for which he received more than 1600 citations.
Dr. Péter B. Barna focused his research to solid state physics/materials science of thin films with special attention to surface phenomena, crystal growth and microstructural evolution. He carried out his pioneering work in thin films developing and using UHV in situ transmission electron microscopy of thin film formation. He made remarkable contribution to solid phase reactions and phase transformations in thin films. He has successfully contributed to the structure-property relationships of thin films.
Dr. Péter B. Barna started his research in the field of thin films, where he worked out the concept, the so called insitu electron microscopy of film growth, investigation of thin films together with professors J. Pócza and Á. Barna. These studies on the growth of In films on different substrates revealed by direct imaging and recording on movie the basic processes playing role on structural development of thin films like nucleation, crystal growth, coalescence and growth of grains in already continuous films. As a continuation of this pioneering work the processes of film formation in amorphous films (a-Ge, a-Sb) were successfully studied revealing the inhomogeneous growth observed in most PVD produced amorphous films in the form of a columnar structure and successfully demonstrated that this inhomogeneity is linked to density deficiencies. Also the crystallization processes in amorphous films has been extensively studied by the in-situ technique. The structure-property relations were successfully addressed when the in-situ technique was extended to the electrical and galvanomagnetic measurements. Already the in-situ studies had shown that minor impurities can play decisive role in formation of crystalline and crystallization processes of amorphous films. Consequently P. Barna directed his research effort in this direction and demonstrated together with his PhD students that oxygen impurities strongly influence crystal growth in Al films and play a major role in morphological and texture development of these films. Crystallographic aspects of the interaction were also clarified, showing that oxygen impact on close packed facets of Al is the most effectively influencing step in structural evolution.
The basic knowledge, accumulated for about two decades (from mid 60-s to mid 80-s) was first utilized in a comprehensive view and model (in the form of new structure zone diagrams for one and two component films) and then in contributing to more applied research projects mainly in the field of functional coatings like Al-Sn coating for sliding bearings for the automobile industry and hard coating for machine tools based on metal nitrides and metal carbo-nitrides. In these rather application oriented research projects Peter B. Barna could further develop the general picture and knowledge on the growth and microstructural development of two-(multi)-phase films, where the overgrowing on each other phases can play either an inhibitor or promoter role in crystal growth and morphological development.
The 2010 IUVSTA Prize for Technology was awarded to Professor Seizo Morita of Osaka University “For his outstanding contributions to the development of room temperature atom identification and manipulation using atomic force microscopy”
In an early stage of atomic force microscope (AFM) development, Morita made invaluable contributions in Electrostatic Force Microscopy and Friction Force Microscopy before directing his interest to the more challenging method of noncontact (NC-AFM). NC-AFM reveals true atomic resolution on conductive and nonconductive surfaces. Morita and his research team in the Graduate School of Engineering, Osaka University have succeeded in constructing seminal basis for atom manipulation and atom discrimination (identification) aiming development of nano-materials and nano-devices using ultra-high vacuum NC-AFM with pico-meter resolution (perpendicular to surface), which they constructed by themselves. NC-AFM measures frequency changes of mechanical resonant oscillation of cantilever with sharpened tip apex due to force between the tip-apex-atom and a surface-atom at their different distances. NC-AFM can give clear atomic images without damage to surfaces.
Seizo Morita was first successful in atom manipulation on semiconductor perpendicular and parallel to the surface using the low temperature AFM. His following developments using the ultra-high vacuum AFM allowed for the first time the manipulation of strongly bonded atoms at room temperature. It was spectacularly shown in an experiment where tin atoms on a germanium surface are rearranged to create the chemical symbol Sn. The discovery of the mechanism how to manipulate strongly bonded atoms by exerting controlled forces during each oscillation of the vibrating cantilever is indeed a remarkable achievement. Unlike earlier implementations for building nanostructures, Morita was able to determine the forces involved in the manipulation process itself, both lateral and vertical. This goes far beyond simply building objects, and into the understanding of the process by which the manipulation occurs. This is the essential ingredient in turning nanoprobes into realistic tools, the dream behind many aspects of nanotechnology.
In a further step Professor Morita developed a novel nondestructive spectroscopy method to discriminate and identify individual atoms on surfaces at room temperature. Although there have been previous reports of force-distance ‘spectra’ taken at individual atoms, these were erratic and difficult to implement, and not really practical tools. Morita’s atom tracking method makes the acquisition of force spectra at individual atoms a practical reality and of broad application. This is a major breakthrough, and Morita’s subsequent remarkable discrimination of individual atomic species (Si, Pb, Sn) is proof of the power of the method. It is clear this has taken AFM to a whole new level of potential applications.
All these results provide very clear answers to questions, which people had at the beginning of AFM development, and open a new avenue to nano-technology for nano-materials including insulators. Although those accomplishments are credited to Seizo Morita himself and his coworkers, it is quite clear that he provided the intellectual initiative, motivation, and necessary provisions for the research in his group as the professor.
(The above introduction to the winners and their achievements are provided by Dr. Janez Setina, Institute of Metals and Technology, Ljubljana, Slovenia.)
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