Scientific Program Special Scientific Workshops»Microscopy of Ion Radiation Induced Defects and changes in structure and properties of materials (MIRID) Moderated by Elena I. Suvorova (A.V. Shubnikov Institute of Crystallography RAS, Moscow, Russia) Isabelle Monnet (Centre de recherche sur les Ions, les Matériaux et la Photonique, France) Wednesday afternoon, 31 August, 4:30 6:30 pm, open to all EMC participants Materials under irradiation undergo structural evolutions, which could modify their macroscopic properties (mechanical, electrical, optical, magnetic, superconducting properties). To foresee the consequences of the irradiation, it is necessary to have a complete description of the processes involved in the different stages of the induced modification from the projectile. The modern powerful analytical instruments (transmission electron microscopy, atomic force microscopy, scanning tunneling microscopy) and advanced simulation tools allow for a better understanding of the radiation-induced defect structure and precise evaluation of their concentration in different materials (crystals, glasses, composites, films). We would like to arouse discussion and to bring new information on visualization and quantitative description of irradiation induced effects, new approaches in microscopy methods for fundamental research and industrial development. Participants to the Round Table Discussion (abstracts can be found at the ned of the page) Christina Trautmann (GSI Helmholtzzentrum and Technische Universität Darmstadt, Germany) "Nanostructures produced with energetic heavy ion projectiles" (invited) Jacques Herman O'Connell (Nelson Mandela Metropolitan University, Port Elisabeth, South Africa) "Enhanced latent track formation in the near surface region of certain SHI irradiated oxide ceramics" (invited) Pierre-Eugène Coulon (Ecole polytechnique, Université Paris-Saclay, Palaiseau, France) "(S)TEM study of original nanodevices obtained by the ion-shaping technique" (invited)
William J. Weber (University of Tennessee, USA and Oak Ridge National Laboratory, USA) "Insights on ion induced track formation from aberration corrected scanning transmission electron microscopy" (invited) Auriane Etienne (Groupe de Physique des Matériaux, Université de Rouen Normandie, INSA de Rouen, Normandie Université, France) "GENESIS: A platform for the study and nano analysis of irradiation effects in materials for nuclear application" Marie-France Beaufort (Institut Prime - Département Physique et Mécanique des Matériaux, Chasseneuil, France) "Defects induced by noble gas implantation in Si based materials" Elena I.Suvorova (A.V.Shubnikov Institute of Crystallography of Russian Academy of Sciences, Moscow, Russia) "Improvement of the buffer film adhesion to Hastelloy substrate and stress relaxation in irradiated YBCO-based second-generation coated conductors" The discussed topics will include: Structure of ions tracks formed at swift heavy ion radiation in semiconductors, high temperature superconductors /coated conductors, ceramics, amorphous materials; Contrast of defects images in TEM, STEM, X-ray microanalysis for evaluation of chemical composition, phase composition study with electron (nano)diffraction and diffractograms; Structural modeling and image simulations of defects; Phase transformation, structural disorder and amorphization, nanostructuring; Mechanism of stress relaxation and enhancement of adhesion in multilayered composites. We ask our future speakers to contact us to set up the timetable. Elena SUVOROVA: suvorova@ns.crys.ras.ru; Isabelle MONNET: monnet@ganil.fr Free admission for EMC participants; 70 fee for participants attending only the workshop (registration here) Abstracts NANOSTRUCTURES PRODUCED WITH ENERGETIC HEAVY ION PROJECTILES Christina Trautmann GSI Helmholtzzentrum and Technische Universität Darmstadt, Germany Heavy ions of kinetic energies in the MeV to GeV range offer unique possibilities of modifying materials properties and producing nanostructures. Each projectile creates a cylindrical track with a few nanometers in diameter, consisting of physically and chemically modified material. The small track size in combination with the large ion range (up to 100 µm and more) allows us to overcome limits of planar structuring techniques.
The presentation will discuss numerous track phenomena observed in different material classes with special emphasis to contributions electron microscopy studies have provided to better understand swift heavy ion-induced effects and defects. ENHANCED LATENT TRACK FORMATION IN THE NEAR SURFACE REGION OF CERTAIN SHI IRRADIATED OXIDE CERAMICS Jacques Herman O'Connell Nelson Mandela Metropolitan University, Port Elisabeth, South Africa The material response to swift heavy ion (SHI) irradiation of simple oxides such as TiO 2 and Al 2 O 3 is markedly different in the near surface volume than in the bulk. In this subsurface region, several tens of nm in thickness, the material exhibits a much higher level of damage creation. The enhanced sensitivity of the material in this region is related to the proximity of a free surface and not strongly dependent on electronic stopping power. At least for these materials, the assumption of cylindrical latent tracks is dubious and great care should be taken when inferring track radii from indirect techniques. Direct observation by TEM can also easily lead to grossly overestimated track radii when most standard specimen preparation techniques are employed. In this presentation the detailed track morphology in these materials will be presented as well as suitable specimen preparation protocols for extracting the required track parameters by direct TEM observation. (S)TEM STUDY OF ORIGINAL NANODEVICES OBTAINED BY THE ION-SHAPING TECHNIQUE Pierre-Eugène Coulon 1 Ecole polytechnique, Université Paris-Saclay, Palaiseau, France G. Rizza 1, M. Kobylko 1, S. Perruchas 2, T. Gacoin 2, D. Mailly 3, X. Lafosse 3, C. Ulysse 3, I. Monnet 4, J. Cardin 4, A. Fafin 4, V. Khomenkov 4, C. Dufour 4, M. Kociak 5, A. Losquin 5 1 LSI, Ecole polytechnique, Université Paris-Saclay, Palaiseau, France 2 LPMC, Ecole polytechnique, Université Paris-Saclay, Palaiseau, France 3 LPN, Marcoussis, France 4 CIMAP, Caen, France 5 LPS, Université Paris-Sud, Université Paris-Saclay, Orsay, France In the last years, ion-shaping has been proposed as an innovative and powerful tool to manipulate matter at the nanometer scale. It is based on the possibility to use the energy delivered by the swift heavy ion to modify the morphology of metallic NPs embedded into an ion-deformable amorphous host matrix. In this way, initially spherical NPs can be not only transformed into a variety of morphologies, such that facetted NPs, nanorods, nanowires, prolate hollow NPs, nanochromosomes, but also these ion-shaped NPs can be spatially oriented opening the way to the fabrication of real treedimensional nanocomposites. Besides the fundamental aspects related to the ion-matter interaction, ion-shaping can also be used to give new insights into the plasmonic properties of metallic nanoparticles. Here, STEM-EELS is used to study localized surface plasmon resonances in ion-shaped metallic nanoparticles with a nanometer-scale spatial resolution. These experimental results are simulated using a specifically developed Auxiliary Differential Equations-Finite Difference Time Domain (ADE-FTDT) code and the Metallic NPs Boundary Element Method (MNPBEM) code. Finally, we show that nonlinear optical microscopy based on second-harmonic generation and tightly-focused linear and radial polarizations allows the determination of the orientation of the NPs with a high degree of reliability. The results of the nonlinear measurements are in very good agreement with numerical modeling based on the boundary element method.
INSIGHTS ON ION INDUCED TRACK FORMATION FROM ABERRATION CORRECTED SCANNING TRANSMISSION ELECTRON MICROSCOPY William J. Weber University of Tennessee, Oak Ridge National Laboratory, USA Present day aberration corrected scanning transmission electron microscopy (STEM) provides the capability to perform various types of imaging and spectroscopic techniques. Application of these methods reveals information on atomic arrangements, disordering of cations and anions, morphology, strain, phase transformations, band gap and electronic structure. The atomic and electronic structure analyses of disordered phases formed in an ion track in Gd 2 Ti 2 O 7 have been studied in detail. The capability of depth dependent high angle annular dark field imaging in this material demonstrates reconstructing the 3D morphology of an ion track. The utility of large scale simulations and data analytics in the study of track formation by aberration corrected STEM will also be discussed. GENESIS: A PLATFORM FOR THE STUDY AND NANO ANALYSIS OF IRRADIATION EFFECTS IN MATERIALS FOR NUCLEAR APPLICATION Auriane Etienne 1 1 Groupe de Physique des Matériaux, Université de Rouen Normandie, INSA de Rouen, UMR CNRS 6634, Normandie Université, Avenue de l Université BP 12, 76801 Saint Etienne du Rouvray, France P. Pareige 1, B. Radiguet 1, C. Pareige 1, F. Cuvilly 1, E. Cadel 1, I. Monnet 2, E. Gardès 2, C. Grygiel 2, D. Marie 2, X. Portier 2, S. Bouffard 2, A. Lopez 3, K. Colas 3, B. Verhaeghe 3, M. Jublot 3, O. Rabouille 3, P. Gavoille 3, P. Chapelot 4, P. Yvon 5 2 CIMAP - Centre de recherches sur les Ions, les Matériaux et la Photonique CEA-CNRS, Normandie Université, 6 Bd Maréchal Juin, 14050 Caen France 3 DEN-Service d Etudes des Matériaux Irradiés, CEA, Université Paris-Saclay, F-91191, Gif-sur-Yvette, France 4 DEN-Département des Matériaux pour le Nucléaire, CEA, Université Paris-Saclay, F-91191, Gif-sur-Yvette, France 5 DEN-Direction déléguée aux Activités Nucléaires de Saclay, CEA, Université Paris-Saclay, F-91191, Gif-sur-Yvette, France Nuclear materials undergo degradations due to neutron/matter interaction. The degradation initially occurs at atomic scale. The French GENESIS platform, coordinated by Philippe Pareige and based on a collaboration between GPM Rouen, CIMAP Caen and CEA Saclay, gathers experimental nanoanalysis tools devoted to irradiated and radioactive materials. Results allow understanding, modelling, and finally simulation of the long time behaviour of the nuclear materials. This platform will give access to RX diffractometer, tomographic atom probes, transmission electron microscopy with in-situ experiments (heating, in-situ straining tests, tomography) and dual beam stations for sample preparation in ion irradiated or active materials irradiated in nuclear power plants. Characteristics of the techniques on the GENESIS platform will be described with some results that may be achieved. GENESIS is supported by the Région Haute-Normandie, the Métropole Rouen Normandie, the CNRS via LABEX EMC3, the Région Basse-Normandie, FEDER, the CEA and the French National Research Agency as a part of the program Investissements d avenir with the reference ANR-11-EQPX-0020. DEFECTS INDUCED BY NOBLE GAS IMPLANTATION IN SI BASED MATERIALS Marie-France Beaufort 1 1 Institut Pprime, CNRS Université de Poitiers ENSMA UPR 3346, Département Physique et Mécanique des Matériaux, BP 30179, 86962 Futuroscope Chasseneuil Cedex, France
C. Jiang 1, J. Nicolaï 1, A. Declémy 1, J.F. Barbot 1, E. Oliviero 1, M. Texier 2, S.E. Donnelly 3, J. Hinks 3, M. Vallet 4 2 Aix Marseille Université, CNRS, IM2NP-UMR7334, F-13397 Marseille, France 3 School of computing and Engineering, University of Huddersfield HD1 3DH, UK 4 CSNSM, Univ. Paris-Sud, CNRS-IN2P3, Université Paris-Saclay, Bâtiment 108, 91405 Orsay, France Silicon based materials (e.g. SiC and Si) are key materials for numerous applications in the nuclear energy field and in the microelectronic industry. It is thus fundamental to study the behavior of this material under ion implantation to a better control for an industrial use. Defects induced by noble gas implantation in Si and 4H-SiC were studied by using a combination of different techniques, namely TEM and DRX. In the case of SiC, after low fluence light ions (He) implantation, and whatever the implant temperature is, the damage accumulation results from ballistic effects only (creation of points defects). But, after implantation under severe conditions, TEM observations show tiny bubbles of nanometer size in a buried damaged layer. Upon annealing at high temperature, the significant increase of surface swelling is observed to be concomitant with the growth of cavities and the formation of extended defects in the highly damaged zone. A detailed analysis by HRTEM experiments and image simulations was carried out in order to characterize the defects leading to the stacking fault pile-up. To determine the effect of the implanted ions on the induced defects, TEM studies of the damage induced by heavy noble gas (Xe) under severe conditions are undertaken. In Si, helium implantation can lead to planar defects named He platelets which could act as precursors to cracks giving rise to the splitting of film (Smart-Cut process). The propagation of cracks is triggered when hydrogen is inserted into the Heplates. The evolution of such He-plates under H-supply was observed in real time by combining ion implantation and TEM imaging by using the MIAMI facility. Results showed that under a limited amount of H, the growth of He-plates resulting from a subcritical stress-corrosion mechanism can be fully described by the kinetic model of Johnson-Mehl-Avrami- Kolmogorov. IMPROVEMENT OF THE BUFFER FILM ADHESION TO HASTELLOY SUBSTRATE AND STRESS RELAXATION IN IRRADIATED YBCO-BASED SECOND-GENERATION COATED CONDUCTORS Elena I. Suvorova A.V. Shubnikov Institute of Crystallography of Russian Academy of Sciences, Moscow Irradiation of YBa 2 Cu 3 O 7-x -based second-generation (2G HTS) coated conductors with 107 MeV 84 Kr 17+ ions resulted in formation of defects, stress relaxation in the composite and improvement of adhesion between buffer films and Hastelloy substrate. TEM analysis and spectrometry data showed that radiation defects in 1-m YBCO layer voids of 3-5 nm in diameter.the density of the defects corresponds to the nominal ion fluency of approximately 10 11 ion/cm 2. Internal stresses in the composite tape were accumulated during the growth of buffer and YBCO layers due to lattice mismatch. It was shown that strain between different lattices is released by the fragmentation of large single crystalline grains in textured buffer layers and formation of nanocrystalline films. Thus heavy ion irradiation results in significant enhancement of YBCO/buffer oxides adhesion to the Hastelloy substrate, reduction of stresses and formation of crack-free structure in the YBCO layer. The use of low dose irradiation enables to increase the critical current and do not lower the transition temperature.