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5. Improved electronic properties of p-epitaxial layers grown on HPHT (100) substrates after a surface pretreatment

Author

Barbay, Cyrille, Mer-Calfati, Christine, Tranchant, Nicolas, Saada, Samuel, Arnault, Jean-Charles, Stenger, Ingrid, Zuerbig, Verena, Lang, N., Kirste, Lutz, Oyelami, Oluwasayo, Eon, David, Laboratoire Capteurs Diamant (LCD-LIST), Département Métrologie Instrumentation & Information (DM2I), Laboratoire d'Intégration des Systèmes et des Technologies (LIST (CEA)), Direction de Recherche Technologique (CEA) (DRT (CEA)), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Direction de Recherche Technologique (CEA) (DRT (CEA)), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Paris-Saclay-Laboratoire d'Intégration des Systèmes et des Technologies (LIST (CEA)), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Paris-Saclay, Groupe d'Etude de la Matière Condensée (GEMAC), Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Centre National de la Recherche Scientifique (CNRS), Fraunhofer Institute for Applied Solid State Physics (Fraunhofer IAF), Fraunhofer (Fraunhofer-Gesellschaft), Institut Néel (NEEL), Centre National de la Recherche Scientifique (CNRS)-Université Grenoble Alpes (UGA)-Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP ), Université Grenoble Alpes (UGA), Hasselt university, and European Project: 640947,H2020,H2020-LCE-2014-1,GreenDiamond(2015)

Subjects
mechanical polishing, diamond, surface roughness, surface pretreatment, etching, boron doping, Thin film, [CHIM.MATE]Chemical Sciences/Material chemistry, crystalline quality, Chemical Vapor Deposition (CVD), dislocations
Abstract

Single-crystal diamond synthesis of high crystaliine quality remains de challenge for power electronic devices. Reaching very smooth substrate surface before Chemical Vapour Deposition (CVD) growth is primordial to better control the crystalline quality of diamond epitaxial layers. We investigaed the effect of Ar/O2 etching on substrates by optimizing the RF-power, the pressure and the O2 content in regard to the etching rate and RMS roughness. Pretreatment efficiency was evaluated by the enhancement of crystalline quality using Raman spectroscopy and High-Resolution X-ray Diffraction.

Published
2018

6. Single α-particle irradiation permits real-time visualization of RNF8 accumulation at DNA damaged sites

Author

Muggiolu, Giovanna, Pomorski, Michal, Claverie, Gérard, Berthet, Guillaume, Mer-Calfati, Christine, Saada, Samuel, Devès, Guillaume, Simon, Marina, Seznec, Hervé, Barberet, Philippe, Centre d'Etudes Nucléaires de Bordeaux Gradignan (CENBG), Université Sciences et Technologies - Bordeaux 1 (UB)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Centre National de la Recherche Scientifique (CNRS), Laboratoire Capteurs Diamant (LCD-LIST), Département Métrologie Instrumentation & Information (DM2I), Laboratoire d'Intégration des Systèmes et des Technologies (LIST (CEA)), Direction de Recherche Technologique (CEA) (DRT (CEA)), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Direction de Recherche Technologique (CEA) (DRT (CEA)), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Paris-Saclay-Laboratoire d'Intégration des Systèmes et des Technologies (LIST (CEA)), and Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Paris-Saclay

Subjects
instrumentation, radiation-induced damage, Recombinant Fusion Proteins, Ubiquitin-Protein Ligases, Membranes, Artificial, Alpha Particles, Time-Lapse Imaging, alpha-rays, Article, DNA-Binding Proteins, Histones, diamond, Genes, Reporter, radioactivity, Cell Line, Tumor, [PHYS.PHYS.PHYS-MED-PH]Physics [physics]/Physics [physics]/Medical Physics [physics.med-ph], nano-crystalline diamond, Humans, boron doping, [PHYS.PHYS.PHYS-INS-DET]Physics [physics]/Physics [physics]/Instrumentation and Detectors [physics.ins-det], ionizing radiation, nuclear instrumentation, radiotherapy, DNA Damage
Abstract

International audience; As well as being a significant source of environmental radiation exposure, α-particles are increasingly considered for use in targeted radiation therapy. A better understanding of α-particle induced damage at the DNA scale can be achieved by following their tracks in real-time in targeted living cells. Focused α-particle microbeams can facilitate this but, due to their low energy (up to a few MeV) and limited range, α-particles detection, delivery, and follow-up observations of radiation-induced damage remain difficult. In this study, we developed a thin Boron-doped Nano-Crystalline Diamond membrane that allows reliable single α-particles detection and single cell irradiation with negligible beam scattering. The radiation-induced responses of single 3 MeV α-particles delivered with focused microbeam are visualized in situ over thirty minutes after irradiation by the accumulation of the GFP-tagged RNF8 protein at DNA damaged sites.

Published
2017
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11. Optimization of the efficiency of diamond based alpha-sensors for spectrometry in aqueous solutions

Author

Tran, Quang Thuan, de Sanoit, Jacques, Pomorski, Michal, Mer-Calfati, Christine, Bergonzo, P., Laboratoire Capteurs et Architectures Electroniques (LCAE), Département Métrologie Instrumentation & Information (DM2I), Laboratoire d'Intégration des Systèmes et des Technologies (LIST), Direction de Recherche Technologique (CEA) (DRT (CEA)), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Direction de Recherche Technologique (CEA) (DRT (CEA)), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Paris-Saclay-Laboratoire d'Intégration des Systèmes et des Technologies (LIST), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Paris-Saclay, ANR-11-SECU-0008,ActiFind,Traces d'émetteurs alpha dans les réseaux publics: de la détection directe en phase liquide à l'identification(2011), Laboratoire d'Intégration des Systèmes et des Technologies (LIST (CEA)), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Paris-Saclay-Laboratoire d'Intégration des Systèmes et des Technologies (LIST (CEA)), and D. Morelli (IEEE)

Subjects
aqueous solutions, spectroscopic stability, current density, diamond based alpha-sensors, thin film, alpha-particle spectroscopy in liquid media, decontamination loops, trace detection, electrolytes, doped diamond electrode, [PHYS.NEXP]Physics [physics]/Nuclear Experiment [nucl-ex], [CHIM.INOR]Chemical Sciences/Inorganic chemistry, sensor area, spectrometry, liquid media, anodic current, alpha particle spectroscopy, diamond, sensor, actinide collection, alpha emitter species, alpha-particle spectrometers, boron doped nanocrystalline diamond film, [PHYS.PHYS.PHYS-INS-DET]Physics [physics]/Physics [physics]/Instrumentation and Detectors [physics.ins-det], Terms-boron doped nanocrystalline diamond, pH fine tuning, electroprecipitation, actinides electroprecipitation, pH, silicon device, alpha-particle detection, p-i-n diodes, alpha activity, precipitation loops, decontamination, silicon PIN diode alpha sensor, electrochemical cell, precipitation duration, silicon radiation detectors, alpha particle detection, radioactivity, electrodeposition, ionizing radiation, liquid solutions, electrochemical electrodes, precipitation (physical chemistry), optimization, electrochemical deposition
Abstract

International audience; Alpha particles detection in liquid media remains challenging since alpha particles are self-absorbed by a few micrometers of liquid. Conventional techniques consist of electrodepositing alpha emitter species on a surface and counting alpha particles using e.g. a silicon device. We have presented a novel approach associating a boron doped nanocrystalline diamond film to a silicon PIN diode alpha sensor. In our devices, actinides collection is performed using a novel method based on electroprecipitation that can be carried out in the solution itself via the use of a doped diamond electrode. The device enables to directly probe both alpha activity as well as energy in liquid solutions. This work demonstrated that the detection of alpha particles is made feasible directly in liquid media. Here we present recent progress addressing the optimization of the actinides electroprecipitation step on the diamond/silicon sensor. The approach is based on the fine tuning of the pH of the electrolyte, the nature of the supporting electrolytes Na2SO4 and NaNO3, the geome1try of the electrochemical cell, the current density value, the precipitation duration and the sensor area. The efficiency of the deposition was significantly improved with efficiency values reaching for example up to 81.5 % for the electroprecipitation of 5.96 Bq of 241Am on the diamond/silicon sensor. The diamond/silicon sensor can be reused after measurement using fast decontamination at high yields ≥ 99 %: e.g. the deposited 241Am electroprecipitated layer can be rapidly removed by applying an anodic current (+ 2 mA/cm2 for 10 minutes) to the electrode in aqueous solution. The diamond/silicon sensor shows also very high spectroscopic stability after 30 cycles of sensing with precipitation/decontamination loops. This study demonstrated that alpha particles spectroscopy measurements could be practically performed, for the first time, in media composed of aqueous solutions after electrochemical deposition process, with detections limits reaching 0.24 Bq/L. We believe this can be of very high interest for alpha spectroscopy in liquids for trace detection.

Published
2013
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12. Publisher's note : Boron-deuterium complexes in diamond: How inhomogeneity leads to incorrect carrier type identification

Author

Kumar, Amit, Pernot, Julien, Omnès, Franck, Muret, Pierre, Traoré, Aboulaye, Magaud, Laurence, Deneuville, Alain, Habka, N., Barjon, Julien, Jomard, François, Pinault, Marie-Amandine, Chevallier, Jacques, Mer-Calfati, Christine, Arnault, Jean-Charles, Bergonzo, Philippe, Semi-conducteurs à large bande interdite (SC2G), Institut Néel (NEEL), Université Joseph Fourier - Grenoble 1 (UJF)-Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP )-Centre National de la Recherche Scientifique (CNRS)-Université Joseph Fourier - Grenoble 1 (UJF)-Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP )-Centre National de la Recherche Scientifique (CNRS), Systèmes hybrides de basse dimensionnalité (HYBRID), Groupe d'Etude de la Matière Condensée (GEMAC), Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Centre National de la Recherche Scientifique (CNRS), Laboratoire d'Intégration des Systèmes et des Technologies (LIST), Direction de Recherche Technologique (CEA) (DRT (CEA)), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA), Semi-conducteurs à large bande interdite (NEEL - SC2G), Systèmes hybrides de basse dimensionnalité (NEEL - HYBRID), and Laboratoire d'Intégration des Systèmes et des Technologies (LIST (CEA))

Subjects
[PHYS.COND.CM-MS]Physics [physics]/Condensed Matter [cond-mat]/Materials Science [cond-mat.mtrl-sci], ComputingMilieux_MISCELLANEOUS
Abstract

International audience

Published
2011
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13. Electrically active defects in boron doped diamond homoepitaxial layers studied from deep level transient spectroscopies and other techniques

Author

Muret, Pierre, Kumar, Amit, Volpe, Pierre-Nicolas, WADE, Mamadou, Pernot, Julien, Magaud, Laurence, Mer-Calfati, Christine, Bergonzo, Philippe, Semi-conducteurs à large bande interdite (SC2G), Institut Néel (NEEL), Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP )-Centre National de la Recherche Scientifique (CNRS)-Université Joseph Fourier - Grenoble 1 (UJF)-Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP )-Centre National de la Recherche Scientifique (CNRS)-Université Joseph Fourier - Grenoble 1 (UJF), Systèmes hybrides de basse dimensionnalité (HYBRID), Laboratoire d'Intégration des Systèmes et des Technologies (LIST), Direction de Recherche Technologique (CEA) (DRT (CEA)), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA), Semi-conducteurs à large bande interdite (NEEL - SC2G), Université Joseph Fourier - Grenoble 1 (UJF)-Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP )-Centre National de la Recherche Scientifique (CNRS)-Université Joseph Fourier - Grenoble 1 (UJF)-Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP )-Centre National de la Recherche Scientifique (CNRS), Systèmes hybrides de basse dimensionnalité (NEEL - HYBRID), and Laboratoire d'Intégration des Systèmes et des Technologies (LIST (CEA))

Subjects
homoepitaxial films, boron doped diamond, PACS 68.55.Ln, 71.55.Cn, 78.60.Hk, 81.05.Uw, [PHYS.COND.CM-GEN]Physics [physics]/Condensed Matter [cond-mat]/Other [cond-mat.other], deep level transient spectroscopy, [SPI.NANO]Engineering Sciences [physics]/Micro and nanotechnologies/Microelectronics, electrically active defects
Abstract

International audience; Homoepitaxial thin films of boron doped diamond are investigated with the help of Fourier transform deep level transient spectroscopy (FT-DLTS) and high resolution isothermal transient spectroscopy (HR-ITS) in order to determine the properties of hole traps. Conductivity studies and other characterisation techniques of defects are also used to bring complementary information. The main conclusions are as follows: (i) many hole traps can be found with activation energies in the range 0.9-1.6 eV; (ii) most of them showinwards decreasing concentrations, which passes below 10^15/cm3 at a depth close to a few hundred nanometers from the surface; (iii) some of them are metastable, in the sense the emission rate distribution undergoes changes after thermal treatments performed at temperatures well belowthose used for growth and previous annealing. These two last facts suggest that hydrogen atoms may be involved in charged defects. In other samples, an irreversible decrease of the conductivity correlated with the increase of the cathodoluminescence (CL)Aband demonstrates that a deep donor is connected with dislocations and acts as a very efficient compensating centre in the first 400 nm just below the surface but with a decreasing concentration deeper inside the homoepitaxial layer. The physical origin of these deep levels is discussed and believed to be likely connected with hydrogen atoms.

Published
2009
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15. Single $\alpha$-particle irradiation permits real-time visualization of RNF8 accumulation at DNA damaged sites

Author

Muggiolu, Giovanna, Pomorski, Michal, Claverie, Gérard, Berthet, Guillaume, Mer-Calfati, Christine, Saada, Samuel, Devès Guillaume, Simon, Marina, Seznec, Hervé, Barberet, Philippe, Centre d'Etudes Nucléaires de Bordeaux Gradignan (CENBG), Université Sciences et Technologies - Bordeaux 1-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Centre National de la Recherche Scientifique (CNRS), Laboratoire d'Intégration des Systèmes et des Technologies (LIST), Direction de Recherche Technologique (CEA) (DRT (CEA)), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Paris-Saclay, and Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)

Subjects
[PHYS]Physics [physics]
Abstract

International audience; As well as being a significant source of environmental radiation exposure, α-particles are increasinglyconsidered for use in targeted radiation therapy. A better understanding of α-particle induced damageat the DNA scale can be achieved by following their tracks in real-time in targeted living cells. Focusedα-particle microbeams can facilitate this but, due to their low energy (up to a few MeV) and limitedrange, α-particles detection, delivery, and follow-up observations of radiation-induced damage remaindifficult. In this study, we developed a thin Boron-doped Nano-Crystalline Diamond membrane thatallows reliable single α-particles detection and single cell irradiation with negligible beam scattering.The radiation-induced responses of single 3MeV α-particles delivered with focused microbeam arevisualized in situ over thirty minutes after irradiation by the accumulation of the GFP-tagged RNF8protein at DNA damaged sites.

Full Text
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