Channelling can have a profound effect on both the defect formation and the distribution of implanted atoms in crystalline materials. This holds particularly for SiC, where channelling effects are well known for conventional dopant impurities. In contrast, channelling effects for protons in SiC are much less studied, despite H is known to be a promising element for defect engineering in power device applications as well as quantum technologies. In this study, the effects of ion channelling on the depth distribution of medium energy proton implants in epitaxial 4H-SiC were investigated. N-type 4H-SiC epilayers, grown on the (0001) plane, were implanted with 350 keV protons to low (5e9 cm-2 ) and medium (6e14 cm-2 ) doses, with beam alignment ranging from 0 degrees to 7 degrees off the [0001] orientation towards the [1120] direction. The samples were measured by a combination of deep level transient spectroscopy (DLTS) and dynamic secondary ion mass spectrometry (D-SIMS), to reveal the role of ion channelling on the generation of defects and the distribution of implanted H. The experimental profiles were also compared to Monte Carlo binary collision approximation (MC-BCA) simulations. These measurements show that channelling implantation of protons in high quality epitaxial 4H-SiC can be used for discrete profile shape adjustments and peak depth control by playing with the beam alignment conditions, thus representing a valuable means for high precision localized in-depth control of electrically active defects.

Lithium dendrites belong to the key challenges of solid-state battery research. They are unavoidable due to the imperfect nature of surfaces containing defects of a critical size that can be filled by lithium until fracturing the solid electrolyte. The penetration of Li metal occurs along the propagating crack until a short circuit takes place. It is hypothesized that ion implantation can be used to introduce stress states into Li6.4La3Zr1.4Ta0.6O12 which enables an effective deflection and arrest of dendrites. The compositional and microstructural changes associated with the implantation of Ag-ions are studied via atom probe tomography, electron microscopy, and nano X-ray diffraction indicating that Ag-ions can be implanted up to 1 µm deep and amorphization takes place down to 650-700 nm, in good agreement with kinetic Monte Carlo simulations. Based on diffraction results pronounced stress states up to -700 MPa are generated in the near-surface region. Such a stress zone and the associated microstructural alterations exhibit the ability to not only deflect mechanically introduced cracks but also dendrites, as demonstrated by nano-indentation and galvanostatic cycling experiments with subsequent electron microscopy observations. These results demonstrate ion implantation as a viable technique to design "dendrite-free" solid-state electrolytes for high-power and energy-dense solid-state batteries.

SmallVolume 20, Issue 12 2470097 FrontispieceFree Access Deflecting Dendrites by Introducing Compressive Stress in Li7La3Zr2O12 Using Ion Implantation (Small 12/2024) Florian Flatscher, Florian Flatscher Department of Materials Science and Engineering, NTNU Norwegian University of Science and Technology, Trondheim, 7491 Norway Christian Doppler Laboratory for Solid-State Batteries, NTNU Norwegian University of Science and Technology, Trondheim, 7491 NorwaySearch for more papers by this authorJuraj Todt, Juraj Todt Chair of Materials Physics, Montanuniversität Leoben and Erich Schmid Institute for Materials Science, Austrian Academy of Sciences, Leoben, 8700 AustriaSearch for more papers by this authorManfred Burghammer, Manfred Burghammer European Synchrotron Radiation Facility, 6 rue Jules Horowitz, BP220, Grenoble, cedex 9, 38043 FranceSearch for more papers by this authorHanne-Sofie Søreide, Hanne-Sofie Søreide Department of Materials Science and Engineering, NTNU Norwegian University of Science and Technology, Trondheim, 7491 NorwaySearch for more papers by this authorLukas Porz, Lukas Porz Department of Materials Science and Engineering, NTNU Norwegian University of Science and Technology, Trondheim, 7491 NorwaySearch for more papers by this authorYanjun Li, Yanjun Li Department of Materials Science and Engineering, NTNU Norwegian University of Science and Technology, Trondheim, 7491 NorwaySearch for more papers by this authorSigurd Wenner, Sigurd Wenner SINTEF Industry, Department of Materials and Nanotechnology, Trondheim, 7465 NorwaySearch for more papers by this authorViktor Bobal, Viktor Bobal Department of Physics, University of Oslo, Oslo, 0316 NorwaySearch for more papers by this authorSteffen Ganschow, Steffen Ganschow Leibniz-Institut für Kristallzüchtung, Berlin , GermanySearch for more papers by this authorBernhard Sartory, Bernhard Sartory Materials Center Leoben, Leoben, 8700 AustriaSearch for more papers by this authorRoland Brunner, Roland Brunner Materials Center Leoben, Leoben, 8700 AustriaSearch for more papers by this authorConstantinos Hatzoglou, Constantinos Hatzoglou Department of Materials Science and Engineering, NTNU Norwegian University of Science and Technology, Trondheim, 7491 NorwaySearch for more papers by this authorJozef Keckes, Jozef Keckes Chair of Materials Physics, Montanuniversität Leoben and Erich Schmid Institute for Materials Science, Austrian Academy of Sciences, Leoben, 8700 AustriaSearch for more papers by this authorDaniel Rettenwander, Daniel Rettenwander Department of Materials Science and Engineering, NTNU Norwegian University of Science and Technology, Trondheim, 7491 Norway Christian Doppler Laboratory for Solid-State Batteries, NTNU Norwegian University of Science and Technology, Trondheim, 7491 NorwaySearch for more papers by this author Florian Flatscher, Florian Flatscher Department of Materials Science and Engineering, NTNU Norwegian University of Science and Technology, Trondheim, 7491 Norway Christian Doppler Laboratory for Solid-State Batteries, NTNU Norwegian University of Science and Technology, Trondheim, 7491 NorwaySearch for more papers by this authorJuraj Todt, Juraj Todt Chair of Materials Physics, Montanuniversität Leoben and Erich Schmid Institute for Materials Science, Austrian Academy of Sciences, Leoben, 8700 AustriaSearch for more papers by this authorManfred Burghammer, Manfred Burghammer European Synchrotron Radiation Facility, 6 rue Jules Horowitz, BP220, Grenoble, cedex 9, 38043 FranceSearch for more papers by this authorHanne-Sofie Søreide, Hanne-Sofie Søreide Department of Materials Science and Engineering, NTNU Norwegian University of Science and Technology, Trondheim, 7491 NorwaySearch for more papers by this authorLukas Porz, Lukas Porz Department of Materials Science and Engineering, NTNU Norwegian University of Science and Technology, Trondheim, 7491 NorwaySearch for more papers by this authorYanjun Li, Yanjun Li Department of Materials Science and Engineering, NTNU Norwegian University of Science and Technology, Trondheim, 7491 NorwaySearch for more papers by this authorSigurd Wenner, Sigurd Wenner SINTEF Industry, Department of Materials and Nanotechnology, Trondheim, 7465 NorwaySearch for more papers by this authorViktor Bobal, Viktor Bobal Department of Physics, University of Oslo, Oslo, 0316 NorwaySearch for more papers by this authorSteffen Ganschow, Steffen Ganschow Leibniz-Institut für Kristallzüchtung, Berlin , GermanySearch for more papers by this authorBernhard Sartory, Bernhard Sartory Materials Center Leoben, Leoben, 8700 AustriaSearch for more papers by this authorRoland Brunner, Roland Brunner Materials Center Leoben, Leoben, 8700 AustriaSearch for more papers by this authorConstantinos Hatzoglou, Constantinos Hatzoglou Department of Materials Science and Engineering, NTNU Norwegian University of Science and Technology, Trondheim, 7491 NorwaySearch for more papers by this authorJozef Keckes, Jozef Keckes Chair of Materials Physics, Montanuniversität Leoben and Erich Schmid Institute for Materials Science, Austrian Academy of Sciences, Leoben, 8700 AustriaSearch for more papers by this authorDaniel Rettenwander, Daniel Rettenwander Department of Materials Science and Engineering, NTNU Norwegian University of Science and Technology, Trondheim, 7491 Norway Christian Doppler Laboratory for Solid-State Batteries, NTNU Norwegian University of Science and Technology, Trondheim, 7491 NorwaySearch for more papers by this author First published: 22 March 2024 https://doi.org/10.1002/smll.202470097AboutPDF ToolsRequest permissionExport citationAdd to favoritesTrack citation ShareShare Give accessShare full text accessShare full-text accessPlease review our Terms and Conditions of Use and check box below to share full-text version of article.I have read and accept the Wiley Online Library Terms and Conditions of UseShareable LinkUse the link below to share a full-text version of this article with your friends and colleagues. Learn more.Copy URL Share a linkShare onEmailFacebookTwitterLinkedInRedditWechat Graphical Abstract Solid-State Electrolytes Compressive stress is caused in Li6.4La3Zr1.4Ta0.6O12 by implanting Ag ions into the near surface region. This compressive stress enables the deflection of mechanically induced cracks, created via nano-indentation as well as growing dendrites during galvanostatic cycling experiments. This demonstrates ion implantation as a viable technique to design "dendrite-free" solid-state electrolytes. More In article number 2307515, Daniel Rettenwander and co-workers. Volume20, Issue12March 22, 20242470097 RelatedInformation

The fabrication of power semiconductor devices based on 4H-silicon carbide (SiC) typically includes doping by ion implantation and postimplantation annealing to activate the implanted dopants. The high-temperature annealing process can initiate various diffusion mechanisms that alter the initial implantation profile in terms of spatial distribution and doping concentration. To investigate the diffusion of aluminum, the main p-dopant in 4H-SiC, samples are prepared by ion implantation and subsequent annealing at 1650 °C for 30 min. Secondary ion mass spectrometry (SIMS) measurements before and after the annealing process are performed to monitor the aluminum concentration. A significant amount of aluminum moves toward the surface and into the lateral direction, which is shown to be directly related to the implantation-induced point defects. Transmission electron microscopy (TEM) images support the discussion of diffusion mechanisms and their dependence on the defect type.

Ion implantation is a crucial step in the process of SiC device fabrication. Precise and predictable doping distributions are necessary for reduced cell pitches and integrated circuit development. However, straggling due to ion channeling affects this goal. Even though vertical channeling has been investigated successfully, lateral straggling remains unclear. Therefore, two-dimensional SIMS concentration distributions are used to investigate lateral straggling of Al and P implanted in 4H-SiC. Results, for both Al and P, show that there is a significant influence of the crystal orientation showing that some channels lead to a few micrometers more lateral straggling than others. High implantation doses increase the amount of amorphization, which leads to more dechanneling and, thus, less straggling. Even though elevated implantation temperatures increase lattice vibrations and thus act in favor of dechanneling, the implantation distributions show significant lateral straggling as amorphization is suppressed.

The carbon vacancy (VC) is a major point defect in high-purity 4H-SiC epitaxial layers limiting the minority charge carrier lifetime. In layers grown by chemical vapor deposition techniques, the VC concentration is typically in the range of 1012 cm-3 and after device processing at temperatures approaching 2000 °C, it can be enhanced by several orders of magnitude. In the present contribution, we show that the cooling rate after high-temperature processing has a profound influence on the resulting VC concentration where a slow rate promotes elimination of VC. Further, isochronal annealing of as-grown and as-oxidized epi-layers protected by a carbon-cap was undertaken between 800 °C and 1600 °C. The results reveal that thermodynamic equilibrium of VC is established rather rapidly at moderate temperatures, reaching a VC concentration of only a few times 1011 cm-3 after 40 min at 1500 °C. Hence, the concept of eliminating VC’s by annealing at moderate temperatures under C-rich equilibrium conditions shows great promise and enables re-annealing of high-temperature processed wafers, in contrast to the procedures commonly used today to eliminate VC. In-diffusion of carbon interstitials and out-diffusion of VC’s are discussed as the kinetics processes establishing the thermodynamic equilibrium

The evolution of irradiation-induced and hydrogen-related defects in n-type silicon in the temperature range 0 – 300 °C has been studied by deep level transient spectroscopy (DLTS) and minority carrier transient spectroscopy (MCTS). Implantation of a box-like profile of hydrogen was performed into the depletion region of a Schottky diode to undertake the DLTS and MCTS measurements. Proportionality between the formation of two hydrogen-related deep states and a decrease of the vacancy-oxygen center concentration was found together with the appearance of new hydrogen-related energy levels.