), nano-objects (nano-particles, nano-wires, nano-bubbles) and the simulation of neutron irradiation effects in nuclear materials (UO 2.

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1 SEMIRAMIS Since the sixties, SEMIRAMIS has developed skills in ion source and ion beam handling ranging from a few hundred ev to around 10 MeV, with the goal of materials implantation, irradiation and analysis as well as isotope separation for target creation. Its equipment includes a 2MV Van der Graaff/Tandem accelerator, ARAMIS; a 190kV implantor, IRMA; a 60kV isotope separator, SIDONIE; and a 200kV Transmission Electron Microscope, TEM. The JANNuS-Orsay platform, started in 2009, provides 12 weeks of beam-time for experimental projects selected by EMIR, a national network concerning material studies under irradiation. The following describes the JANNuS-Orsay facility, its integration within the EMIR network and the instruments managed by the department and concludes with a summary of the beam time s use. 1. Now in the Instrumentation 2. Now in the Computing 1 2 Members: Cyril Bachelet, Jerôme Bourçois, Laurent Delbecq, Franck Fortuna 1, Odile Kaitasov, Dominique Le Du 1, Jérémy Moeyaert, Erwan Oliviero, Sandrine Picard, Sebastien Pitrel 1,Tony Viaud 2 JANNuS/EMIR JANNuS-Orsay is a multi-ion beam irradiation platform dedicated to the controlled modification or synthesis of materials at the nanoscale by ion implantation and irradiation, the simulation of radiation damage in nuclear materials, and education and training in the field of particle-matter interactions and its applications. It is comprised of a 2 MV Tandem/Van de Graaf Accelerator (ARAMIS) and a 190 kv ion implantor (IRMA) coupled to a 200 kv Transmission Electron Microscope (TEM FEI Tecnai G 2 20) allowing in-situ observation of irradiation effects (Figure 1). The project was launched in 2004, and the platform has been open to the international scientific community since March, Since the opening, JANNuS-Orsay has hosted scientists from all around the world wishing to carry out ion beam irradiation/implantation in-situ experiments in the TEM. The experiments performed at JANNuS- Orsay mainly concerned irradiation/implantation effects on semiconducting materials (Si, SiC, Ge, SiGe), insulating materials (SiO 2, Si 3 N 4 ), nano-objects (nano-particles, nano-wires, nano-bubbles) and the simulation of neutron irradiation effects in nuclear materials (UO 2, FeCr alloys, ODS, glass, MAX phases). These experiments have produced 12 publications, 5 PhDs and 35 presentations at international congresses. JANNuS-Orsay is a part of the JANNuS platform, managed by CEA/DEN, CEA/INSTN, CNRS/IN2P3 and Paris-Sud University, in the framework of a Scientific Interest Group (GIS). A scientific committee initially assessed the concerned projects, but now the EMIR network s own committee has replaced it. In 2009, the Semiramis group was highly involved in the setup of the EMIR network, as desired by CNRS and CEA with the agreement of the French Ministry of Higher Education and Research. This network consists of five accelerator platforms dedicated to material irradiation (CIMAP-GANIL, CEMH- TI-Orléans, LSI-Palaiseau, JANNuS-Saclay and JANNuS-Orsay) with a shared scientific committee. An interactive website (designed and maintained by the Computing department) for the submission of proposals for experiments on the accelerators belonging to the entire network was opened ( and includes a set of technical information on each facilities. Figure 1 General overview of the JANNuS-Orsay platform.

2 Three RFP s were sent out with the number of applications increasing each year (30 in 2009, 61 in 2010, 65 in 2011 for all the platforms). The Program Advisory Committee reviews the proposals while assessing their scientific quality and feasibility in accordance with the characteristics of the requested accelerators. Another network s activity involves the organization of events related to material irradiation and induced modifications. In October 2011, the first EMIR network users day took place at the Laboratoire de l Accélérateur Linéaire in Orsay. Organized by the CSNSM, it hosted 100 users and students. ARAMIS In activity since 1989, ARAMIS is an in-house developed 2MV s accelerator for materials implantation/ irradiation and ion beam analysis. ARAMIS can be used as a Van der Graaff accelerator, with a Penning ion source located at the high voltage stage, and provides gaseous elements like hydrogen, helium, nitrogen or oxygen. ARAMIS can also be used as a Tandem, with the Middleton negative ion source at the ground potential, and provides more than forty different elements. See Figure 2 for the elements available with ARAMIS. The implantation/irradiation beam line is used for materials modifications with several conditions. Different sample holders are available and enable materials implantation/irradiation with temperatures ranging from 77K to 1200K. Others enable implantation/irradiation on different samples with different parameters in the same run, with holders such as Translation, Revolver or Airlock. The third beam line, called the JANNuS line, involves a connection from ARAMIS to the Transmission Electron Microscope (TEM). It allows in situ studies of materials implantation/irradiation under the double ion beam of ARAMIS and IRMA (see JANNuS section). A forth beam line is currently under development which will link ARAMIS and IRMA and allow in situ ion beam analysis of materials implantation/irradiation. 3. Thanks to the RESET 3 Three beam lines are available for different types of experiments. The characterization line is used for ion beam materials analysis. A goniometer, with 2 translations and 2 rotations, enables characterization of several samples in the same run as well as channelling inside the material s crystal. The available ion beam analysis methods include C/RBS, ERDA and PIXE. During the last three years, the control and acquisition analysis system has been renovated in two steps. The goniometer control was updated with a PMC Multiflex card, instead of an old RS232 controller, and a LabView-based user interface. The C/RBS acquisition analogic system was also replaced with a CAEN N1728B. This module enables signal digitizing from the preamplifier on 4 different channels. A new user acquisition interface was developed using LabView. The possibility to use 4 detectors simultaneously is currently under development. This option will reduce the acquisition time or increase the counting rate of the spectra. Figure 2 Elements available with ARAMIS (blue squares). C. Bachelet /CSNSM During the spring of 2010, the high-energy accelerator tube was changed. The accelerator tube is the component transporting the ion beam between the high-voltage to the ground potential. The tube is a pile of titanium plates and glass rings which are stuck together. A leak in the tube, caused by a crack in the glass, impaired the accelerator s functioning for several months. The replacement caused a shutdown of the accelerator for another three months (Figure 3). In 2012, ARAMIS successfully passed the decennial pressure test 3. Figure 3 High-energy accelerator tube replacement. 13 Finally, PIXE analysis was added two years ago. Two silicon drift detectors (SiLi-SDD) create the possibility to detect elements from beryllium to uranium. 99

3 IRMA Developed in-house in 1979, IRMA is an ion implanter of 190kV. IRMA can provide ion beam energy ranging from 5 to 570 kev. Its Bernas-Nier ion source can produce almost all stable elements (Figure 4), with a current up to 100 µa. The purpose of IRMA is principally materials modification by ion implantation, in several conditions. The samples holders available for IRMA are the same as those described in the ARAMIS section above. During the last few years, taking advantage of JANNuS platform developments, IRMA benefited from several updates and improvements. For example, the beam line behind the acceleration section has been renovated and now all the components at ground potential are computer-driven. Some components at the high voltage stage will undergo a complete migration to digital control in early A replacement of the moving source electrode is also on schedule. A complete new design with motorised and independent movements has been developed in collaboration with the mechanical engineering department (Figure 5). The installation of this electrode will be coupled with a control update, since the movements will be computer-driven. Transmission Electron Microscope (TEM) As explained above, the TEM is part of the JANNuS- Orsay platform and has been designed for in-situ and dynamic experiments. Therefore, it is mainly devoted to JANNuS experiments. However, it also offers a truly universal imaging and analysis solution for ex-situ experiments or other studies. The TEM is a FEI Tecnai G 2 20 Twin. The electron beam is extracted from a LaB 6 filament and the accelerating voltage can be set from 80 to 200 kv. The spatial resolution is 0.27 nm. For imaging, two CCD cameras are available: a wide angle (Gatan Erlangshen ES500W) and a high resolution (Gatan Orius 200) both allowing in-situ movie recording. The TEM is well equipped for quantitative analysis with EDX, GIF for EELS and EFTEM studies. It allows advanced scanning transmission electron microscopy (S)TEM with HAADF and BF-DF detectors. It also has a wide range of sample holders (11 holders!): from room temperature holders (single, double-tilt, rotation) to heating holders (800 C, 1000 C, 1300 C) to cooling holders (LN 2 ), and ultra-thin sample holders especially designed for in-situ irradiation. Studies developed with the TEM, apart from JANNuS experiments, are in the fields of materials sciences, nanotechnology and semiconductors and mainly involved nanoparticles studies, amorphization/recrystallization, studies of dislocation loops in alloys etc. Figure 4 The elements available with IRMA (blue squares). C. Bachelet /CSNSM A new 3D imaging (tomography) is also available both in conventional or STEM-HAADF mode. A Hollow-Cone Dark Field (HCDF) has been also developed. Figure 5 New source electrode (designed and mounted by the mechanical engineering department). 100

4 SIDONIE SIDONIE is an electromagnetic isotope separator which is primarily used for the preparation of high purity thin deposit and targets, mainly in nuclear physics experiments. Figure 6 SIDONIE. The separator is composed of a Bernas-Nier ion source, a high resolution analysing magnet and a collecting device which is used to prepare targets with the selected ion beam. A picture of the SIDONIE experimental apparatus is represented in Figure 6. The ions produced are mainly single-charged and the extracted beam intensity ranges from a few ma up to 20 ma. Its energy is typically around 40 kev. The analysing magnet has been designed to separate ion beams of mass 230 uma at 50 kev. See Figure 7 for the elements available with SIDONIE. Beam Time Summary The split of the 2012 s beam time is around 40% for CSNSM s research, 35% for EMIR- approved experiments, 20% for external demands and a bit less than 5% for teaching (Figure 8). Teaching was mainly about practical work on ion beam analysis, delivered by personnel of SEMIRAMIS or by members of the PCI research group, and concerned several Masters : Nuclear Energy, Physics and Engineering of Energy, Particle Accelerators and Matter Interactions and Materials Science. The time machine split shows that experiments mostly involved ARAMIS and Dual-beam inside the TEM. During the last few years, beam time on SIDONIE has dropped, but activity should pick-up with the start of several new projects in nuclear physics and astrophysics. Peak activity time for ARAMIS- IRMA-SIDONIE is between 100 an 160 days per year though it reached between 140 and 180 days per year during the last three years. Figure 7 Elements available with SIDONIE (blue squares). C. Bachelet /CSNSM Figure 8 ARAMIS-IRMA-SIDONIE s beam time split for the last three years and the beam time split per machine in

5 Research & Development activities The group mainly conducted research in the field of ion-matter interactions. Ion beams are used for the modification of matter and/or for analysis of matter. For instance, studies of rare gases - semiconductor interactions are in progress (Figure 9) as well as in-situ TEM ion beam modifications of nanoparticles (Figure 10). In September 2012, the ANR HeDiff project was launched in collaboration with geologists with plans to study the He diffusion mechanism in apatites regarding rocks thermochronological dating. The department is also a partner in the CaLIPSO project, a new detector with high-resolution and high-sensitivity for PET oncology scanning. Figure 9 {311} defects obtained after in-situ irradiation of Ne at 170 kev, 750 C in silicon at a fluence of 2E15 at.cm -2. Selected area diffraction pattern showing series of streaks in the four <110> directions typical of {311} defects. Figure 10 General view of the modifications of nanoparticles after in-situ irradiation with 4 MeV Au at a fluence of 2E15 at.cm