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Introduction and objectives: Future physicians are insufficiently prepared for the topic of transgender identity during their studies. Relevant courses during undergraduate medical education are heterogeneous and not widely established within the curricula. At our university, we investigated if students' knowledge of transgender identity could be increased through medical specialist teaching and teaching delivered by representatives of the trans* community (community-supported teaching).Methods: During summer semester 2021 (SS21), the knowledge level on transgender identity of 134 medical students in their fifth clinical semester was evaluated (phase 1). In addition, knowledge gain on gender incongruence through the module "psychiatry" was retrospectively surveyed across two dimensions: 1. diagnostic criteria, 2. treatment/care. During winter semester 2021/22 (WS 21/22), a 90-minute seminar on transgender identity was held either community-supported or by medical specialists (phase 2). Following the psychiatry exam, a re-evaluation was carried out by 115 students (phase 3).Results: The students in SS21 did not feel sufficiently educated in the topic of transgender identity through their studies, but rated the relevance of the topic for their later profession as high. Learning gain improved after the introduction of the seminar in WS21/22 compared to the previous semester (both dimensions p <.001). Community-supported and specialist teaching achieved equivalent results.Conclusion: One 90-minutes seminar led to a significant learning gain regarding the topic of transgender identity. Community-supported teaching is a promising way to impart knowledge in a qualified manner: Medical faculties should use this form of teaching to convey established knowledge to students in future curricula., Zielsetzungen: Zukünftige Ärzt*innen werden im Studium unzureichend auf das Thema Transidentität vorbereitet. Lehrveranstaltungen sind im internationalen Vergleich heterogen und nicht an allen Universitäten etabliert. An unserer Universität wurde untersucht, ob sich das Wissen der Studierenden zu diesem Thema durch fachärztliche Lehre sowie durch Lehre, die von Vertreter*innen der Trans*Community gehalten wurde (communitygestützte Lehre) in ähnlicher Form steigern lässt.Methoden: Im Sommersemester 2021 (SS21) wurde der Wissensstand zu Transidentität von 134 Medizinstudierenden im fünften klinischen Semester evaluiert (Phase 1). Zudem wurde der Lernzuwachs zu Genderinkongruenz durch das Modul Psychiatrie retrospektiv in zwei Dimensionen erfragt: 1. Diagnosekriterien, 2. Behandlung/Begleitung. Im Wintersemester 2021/22 (WS 21/22) wurde ein 90-minütiges Seminar zum Thema Transidentität fachärztlich oder communitygestützt durchgeführt (Phase 2). Im Anschluss an die Klausur Psychiatrie erfolgte eine erneute Evaluation durch 115 Studierende (Phase 3).Ergebnisse: Die Studierenden im SS21 fühlten sich durch ihr Studium nicht ausreichend im Thema Transidentität ausgebildet, schätzten die Relevanz des Themas für ihren späteren Beruf aber hoch ein. Der Lernzuwachs verbesserte sich nach Einführung des Seminars im WS 21/22 im Vergleich zum vorherigen Semester (beide Dimensionen p <,001). Die communitygestützte und die fachärztliche Lehre erzielte gleichwertige Lernzuwächse.Schlussfolgerung: Ein 90-minütiges Seminar führte bei Studierenden zu einem signifikanten Lernzuwachs bezüglich Transidentität. Communitygestützte Lehre ist hierbei eine gute Möglichkeit, Wissen zu vermitteln. Medizinische Fakultäten sollten diese Form der Lehre nutzen, um in zukünftigen Curricula etabliertes Wissen gezielt an Studierenden zu vermitteln.

Fe-9Cr is a model alloy for studying irradiation effects relevant for potential applications of high-chromium ferritic/martensitic steels in nuclear energy devices. Ion irradiation is a tool extensively employed with the aim to emulate the neutron damage characteristic for irradiation environments in fission or fusion reactors. Here we report on STEM studies of the microstructure of ion-irradiated Fe-9Cr with special emphasis on the effects of pre-existing dislocations. Irradiations with 8 MeV Fe3+ ions were carried out at the 3 MV tandetron accelerator at the Ion Beam Center at HZDR. Profiles of displacement damage and implanted ions were calculated using the binary collision code SRIM. Cross-sectional TEM specimens were prepared by focused ion beam lift-out technique using a Thermo Fisher Helios 5CX. The microstructure was studied in a Talos F200X scanning transmission electron microscope. The most striking feature of the irradiated microstructure in the range of high displacement damage, but low concentration of implanted ions, is the presence of helical dislocations. From the results of the Burgers vector analysis we conclude, that the helices were formed from pre-existing straight line dislocations with a dominating screw component. After transformation into the helical shape, the dislocations contain screw, mixed and edge segments. The STEM images also reveal large numbers of small dislocation loops mainly located close to the helices. The presence of helical dislocations and the accumulation of loops close to them resembles observations reported for neutron-irradiated Fe-9Cr. Hence we conclude that - in the depth range of low implanted ion concentration - ion irradiation can produce similar defect configurations like neutron irradiation if the arrangement of pre-existing dislocations is comparable.

This study addresses the complementary metal-oxide-semiconductor-compatible fabrication of vertically stacked Si/SiO2/Si nanopillars (NPs) with embedded Si nanodots (NDs) as key functional elements of a quantum-dot-based, gate-all-around single-electron transistor (SET) operating at room temperature. The main geometrical parameters of the NPs and NDs were deduced from SET device simulations using the nextnano++ program package. The basic concept for single silicon ND formation within a confined oxide volume was deduced from Monte-Carlo simulations of ion-beam mixing and SiOx phase separation. A process flow was developed and experimentally implemented by combining bottom-up (Si ND self-assembly) and top-down (ion-beam mixing, electron-beam lithography, reactive ion etching) technologies, fully satisfying process requirements of future 3D device architectures. The theoretically predicted self-assembly of a single Si ND via phase separation within a confined SiOx disc of < 500 nm³ volume was experimentally validated. This work describes in detail the optimization of conditions required for NP/ND formation, such as the oxide thickness, energy and fluence of ion-beam mixing, thermal budget for phase separation and parameters of reactive ion beam etching. Low-temperature plasma oxidation was used to further reduce NP diameter and for gate oxide fabrication whilst preserving the pre-existing NDs. The influence of critical dimension variability on the SET functionality and options to reduce such deviations are discussed. We finally demonstrate the reliable formation of Si quantum dots with diameters of less than 3 nm in the oxide layer of a stacked Si/SiO2/Si NP of 10 nm diameter, with tunnelling distances of about 1 nm between the Si ND and the neighboured Si regions forming drain and source of the SET.

This study addresses the complementary metal-oxide-semiconductor-compatible fabrication of vertically stacked Si/SiO2/Si nanopillars (NPs) with embedded Si nanodots (NDs) as key functional elements of a quantum-dot-based, gate-all-around single-electron transistor (SET) operating at room temperature. The main geometrical parameters of the NPs and NDs were deduced from SET device simulations using the nextnano++ program package. The basic concept for single silicon ND formation within a confined oxide volume was deduced from Monte-Carlo simulations of ion-beam mixing and SiO x phase separation. A process flow was developed and experimentally implemented by combining bottom-up (Si ND self-assembly) and top-down (ion-beam mixing, electron-beam lithography, reactive ion etching) technologies, fully satisfying process requirements of future 3D device architectures. The theoretically predicted self-assembly of a single Si ND via phase separation within a confined SiO x disc of <500 nm3 volume was experimentally validated. This work describes in detail the optimization of conditions required for NP/ND formation, such as the oxide thickness, energy and fluence of ion-beam mixing, thermal budget for phase separation and parameters of reactive ion beam etching. Low-temperature plasma oxidation was used to further reduce NP diameter and for gate oxide fabrication whilst preserving the pre-existing NDs. The influence of critical dimension variability on the SET functionality and options to reduce such deviations are discussed. We finally demonstrate the reliable formation of Si quantum dots with diameters of less than 3 nm in the oxide layer of a stacked Si/SiO2/Si NP of 10 nm diameter, with tunnelling distances of about 1 nm between the Si ND and the neighboured Si regions forming drain and source of the SET.

Robis requires an Abstract, but this poster doesn't have one, so here's the one from a conference talk about the same contents: We report on 3D lattice kinetic Monte Carlo (3DlkMC) simulation of nanostructure formation during rapid quenching in gas-atomization (up to 108K/s) of droplets of AlSi alloy melt. The nanostructured Si particles (with the Al selectively etched away) promise to enable about 10x the capacity of the current state-of-the-art graphite in lithium-ion batteries by mitigating Si pulverization. This work reproduces the experimentally found nanosponge and core-shell particles and reveals heteronucleation at Al2O3 sites resulting from trace oxygen at the surface as the formation mechanism for core-shell particles. The computer simulation uses a memory-efficient bit-encoded lattice, enabling large scale atomistic calculations, while kinetics is implemented via CPU-efficient bit-manipulation for atom jumps between lattice sites. The jump probabilities are described by the metropolis algorithm with a look-up-table of energies calculated with an angular dependent potential for the Si-Al-Au system in LAMMPS. This work is supported by the federal ministry for economic affairs and climate protection under grant number 01221755/1.

Six carbon atoms of graphite of lithium ion battery (LIB) anodes can store one lithium atom, whereas one Si atom can store nearly four lithium atoms. Theoretically, the replacement of graphite by silicon could reduce the weight of the anode by a factor of nearly 10. However, due to the strong swelling of silicon upon lithiation, Si anodes suffer from pulverization which reduces drastically the life cycle of LIBs. It has been shown that nanostructured silicon with structure sizes <200nm can withstand pulverization. There are many activities to develop an economic large-scale fabrication of such nanosilicon. We form Si nanostructures by phase separation during quenching of AlSi alloy droplets. At atomization of the AlSi melt the microdroplet solidify extremely fast which results in nanoscale Si pattern. Subsequently the Al is removed by selective etching leading to nanoporous Si microspheres. We show that the structure depends strongly on the AlSi composition, the particle sizes and impurities. Promising nanosilicon for LIB anodes with a good cycling have been found. This work is supported by the German federal ministry for economic affairs and climate protection under grant number 01221755/1.

Low-power logic and memory circuits remain a main task for the next generations of energy-efficient electronic devices. Single Electron Transistors (SETs) are extremely low energy dissipation devices. However, SETs operate usually at cryogenic temperatures and have some serious drawbacks. Fortunately, Field Effect Transistors (FETs) and SETs are complementary: The SET is the champion of low-power consumption while FETs advantages, like high-speed, driving, voltage gain and input impedance can compensate exactly for SET's intrinsic drawbacks. To overcome the drawback of cryogenic temperature operation, each SET has to be manufactured with a quantum dot of a size of just a few nanometers, and this dot has to be located not more than about one nanometer apart from the electrodes. The large-scale implementation of SETs in room-temperature electronics is hampered by its unresolved manufacturability because such requirements are beyond the limits of present lithography. We employed self-organization to overcome the present-day limits of lithography. On 5…8nm thick SiO2 layers of (001)Si wafers about 30nm thick a-Si layers have been deposited and subsequently irradiated with 50 keV Si+ ions. The irradiation leads to ion beam mixing at the upper and lower Si/SiO2 interfaces and transforms the buried SiO2 layer to SiOx with x~1. Then, pillar arrays have been fabricated from such layer stacks using electron beam lithography and plasma etching. Arrays of pillars with different diameters from 100nm down to less than 20nm have been produced, where the smallest pillar diameters have been further reduced to ~10nm by plasma oxidation and selective oxide etching (sacrificial oxidation). In this manner we manufactured SiOx disks of ~10nm diameter and 5nm thickness sandwiched between the Si of the pillars. During Rapid Thermal Processing (RTP) of such pillars at 1050°C for 60s, phase separation SiOx  (1-x/2)Si + x/2SiO2 occurs via formation of Si nuclei and Ostwald ripening. Close to

Fe-9Cr is a model alloy for studying irradiation effects that are relevant for potential applications of high-chromium ferritic/martensitic steels in nuclear energy devices. Here we report on scanning transmission electron microscopy (STEM) studies of the microstructure of Fe-9Cr irradiated with 8 MeV Fe3+ ions. Two samples were irradiated with different ion fluences resulting in peak values of displacement damage of 2 and 10 dpa, respectively. The spatial distribution of irradiation-induced dislocation loops was studied with special emphasis on the effects of pre-existing network dislocations. The most striking feature of the irradiated microstructure is the presence of helical dislocations. From comparison of the irradiated layer with the dislocation arrangement in the non-irradiated substrate it is concluded that the helices were formed from straight pre-existing line dislocations that originally had a dominating screw component. Other types of dislocations observed in the material did not adopt a helical shape during irradiation. Decreasing the dose has a significant effect on the helical dislocations, the helices are less developed and have a smaller diameter. For both irradiation conditions, an inhomogeneous distribution of irradiation-induced dislocation loops is observed. A high number of loops is present close to the helical dislocations and also close to dislocations that have not adopted a helical shape. In areas away from the dislocations, the number of visible loops is very low. The loop clustering close to helical dislocations resembles observations reported for neutron irradiated Fe-9Cr. Hence we conclude that ion irradiations can produce similar defect configurations like neutron irradiations when the arrangement of pre-existing dislocations is comparable.

This study analyzes the CMOS compatibility in the manufacturing of a hybrid SET-FET circuit. The fundamental element towards an operating SET at room temperature is a vertical nanopillar with embedded Si nanodot generated by ion-beam irradiation. The integration process from nanopillars to contacted SETs is validated by structural characterization. Then, the monolithic fabrication of planar FETs co-integrated with vertical SETs is presented, and its compatibility with standard CMOS technology is demonstrated. The work includes process optimization, pillar integrity validation, electrical characterization and simulation taking into account parasitic elements. The FET fabrication process is adapted to meet the requirements of the pre-fabricated nanopillars. Overall, this work establishes the groundwork for the realization of a hybrid SET-FET circuit operating at room temperature.

Herausforderungen bei der TEM-Probenpräparation von neuartigen Elektroden-Materialen für Li-Ionen-Batterien

Si as anode material for lithium-ion batteries promises 10x the capacity of state-of-the-art graphite. However, Si anodes suffer from pulverization and electrode collapse due to large volume increase during lithiation. It has been shown that Si structures with sizes below about 200 nm remain stable [1]. Therefore, we try to understand the formation of Si nanosponge in µ-sized particles during quenching of AlSi droplets. Subsequently Al is removed from the as-produced particles by etching. Phase separation of Si and Al upon solidification of the molten AlSi alloy occurs in two stages: First nucleation and growth of primary Si grains and second formation of eutectic sponge in the Si depleted melt, with faster cooling leading to finer structures. Through modelling and simulation, the reaction pathway can be understood, allowing to optimize process parameters. For this, a model was developed, which has as initial state a fully liquid, spherical droplet with random distribution of atom species Al, Si, vacancies and oxygen impurities. A many body angular-dependent potential (ADP) has been employed which reproduces the Al-Si phase diagram quite reasonable. As the melt cools below the liquidus temperature, precipitation of primary Si takes place, followed by spinodal demixing of the melt upon reaching the eutectic. Nucleation is influenced by trace oxygen which modifies surface energies and leads to formation of sites for heteronucleation. The diffusion-reaction behavior of the species, including nucleation and/or spinodal decomposition are simulated with a 3D kinetic lattice Monte Carlo program [2] using the ADP-potential for the Al-Si system [3] with modifications added to model surface oxidation. This program enables large scale calculations by a bit-encoded lattice and lattice jumps via bit-manipulation. Our simulations qualitatively reproduce the Al-Si phase diagram, as well as composition dependent interface energies of solid Si to Al-Si melt and the nucleation behavi

Six carbon atoms of graphite of lithium ion battery (LIB) anodes can store one lithium atom, whereas one Si atom can store nearly four lithium atoms. Theoretically, the replacement of graphite by silicon could reduce the weight of the anode by a factor of nearly 10. However, due to the strong swelling of silicon upon lithiation, Si anodes suffer from pulverization which reduces drastically the life cycle of LIBs. It has been shown that nanostructured silicon with structure sizes <200nm can withstand pulverization. There are many activities to develop an economic large-scale fabrication of such nanosilicon. We form Si nanostructures by phase separation during quenching of AlSi alloy droplets. At atomization of the AlSi melt the microdroplet solidify extremely fast which results in nanoscale Si pattern. Subsequently the Al is removed by selective etching leading to nanoporous Si microspheres. We show that the structure depends strongly on the AlSi composition, the particle sizes and impurities. Promising nanosilicon for LIB anodes with a good cycling have been found. This work is supported by the German federal ministry for economic affairs and climate protection under grant number 01221755/1.

Low-power logic and memory circuits remain a main task for the next generations of energy-efficient electronic devices. Single Electron Transistors (SETs) are extremely low energy dissipation devices. However, SETs operate usually at cryogenic temperatures and have some serious drawbacks. Fortunately, Field Effect Transistors (FETs) and SETs are complementary: The SET is the champion of low-power consumption while FETs advantages, like high-speed, driving, voltage gain and input impedance can compensate exactly for SET's intrinsic drawbacks. To overcome the drawback of cryogenic temperature operation, each SET has to be manufactured with a quantum dot of a size of just a few nanometers, and this dot has to be located not more than about one nanometer apart from the electrodes. The large-scale implementation of SETs in room-temperature electronics is hampered by its unresolved manufacturability because such requirements are beyond the limits of present lithography. We employed self-organization to overcome the present-day limits of lithography. On 5…8nm thick SiO2 layers of (001)Si wafers about 30nm thick a-Si layers have been deposited and subsequently irradiated with 50 keV Si+ ions. The irradiation leads to ion beam mixing at the upper and lower Si/SiO2 interfaces and transforms the buried SiO2 layer to SiOx with x~1. Then, pillar arrays have been fabricated from such layer stacks using electron beam lithography and plasma etching. Arrays of pillars with different diameters from 100nm down to less than 20nm have been produced, where the smallest pillar diameters have been further reduced to ~10nm by plasma oxidation and selective oxide etching (sacrificial oxidation). In this manner we manufactured SiOx disks of ~10nm diameter and 5nm thickness sandwiched between the Si of the pillars. During Rapid Thermal Processing (RTP) of such pillars at 1050°C for 60s, phase separation SiOx  (1-x/2)Si + x/2SiO2 occurs via formation of Si nuclei and Ostwald ripening. Close to

The data included in the publication are results of SET device simulations, Monte-Carlo simulations of physical processes (ion-beam mixing, phase seepration, Si nanodot formation) and micrographs taken by electron and ion microscopes.

Single Electron Transistors (SETs) open the way to semiconductor devices with extremely low power consumption. Quantum mechanical effects are used in such transistors: field-controlled tunneling of single electrons from a source to a drain via a quantum dot. SETs can be manufactured as thin Si pillars (source and drain) with a Si oxide layer in-between containing one Si quantum dot (Fig. 1). After SiOx formation by ion beam mixing, a thermally activated phase separation including Ostwald ripening results in a self-organization of Si nanocrystals in the SiO2 layer acting as Si quantum dots (Si NDs). For SET operation at room temperature, the diameter of the Si pillars needs to be < 12 nm, the Si ND diameter must be in the range of 2…3 nm and the distances between Si NDs and source/drain cannot be larger than 1.5 nm allowing quantum mechanical tunneling of the electrons. Thus, Transmission Electron Microscopy (TEM) must be used for the structural characterization of these SETs. Si NDs inside the SiO2 matrix can only be detected by using the Si plasmon loss in the energy-filtered TEM mode. TEM sample preparation is challenging because of the very small 3D structure of the pillars (Fig.2) and the need for very thin TEM lamellae (30…40 nm in thickness). The Focused Ion Beam (FIB) lift-out technique can be used to prepare such samples. Setting markers and gradual thinning of the lamella from both sides (with TEM inspection in between) is necessary. Surprisingly, comprehensive TEM studies uncovered that the oxide layer of a Si/ SiO2/Si layer stack can become dramatically thinner in pillars fabricated from this stack by Reactive Ion Etching (RIE). The oxide layer thinning depends on the pillar diameter. For instance, an originally 8 nm thick SiO2 layer is reduced to 2.6 nm in 15 nm diameter pillars. In order to prove that this oxide shrinkage is caused by RIE and not by sample preparation the most critical process in the FIB preparation - which is the electron-beam-assisted

Si nanopillars for the fabrication of vertical nanowire gate-all-around Single Electron Transistors [1], have been irradiated with Si++, Pb+, Pb++, Au +, Au++, Au2 +, and Au3 + ions accelerated by 30 kV. A FIB of mass separated ions, extracted from a Liquid Metal Alloy Ion Source [2], has been scanned over regular arrays of Si nanopillars of different diameters and pillar distances. The irradiations have been performed at RT and 400∘C. Different morphological changes of the pillars like thinning, height reduction, tilting etc. have been observed which can be attributed to ion erosion (sputtering), impact-induced viscous flow or even transient nanosecond-scale melting [3]. The pillars were imaged by AFM, SEM, TEM and HIM. 3D Monte Carlo simulations [4] of ion and recoil trajectories based on the Binary Collision Approximation and Molecular Dynamics calculations have been carried out in order to discriminate the dominating processes. [1] EU project Ions4SET, Horizon 2020 grant No. 688072 [2] L.Bischoff, et al., Appl. Phys. Rev. 3 (2016) 021101 [3] C. Anders, K.-H. Heinig, H. Urbassek, Phys. Rev. B87 (2013) 245434 [4] W. Möller,NIM B322 (2014) 23

Ion beam induced amorphization of semiconductor nanostructures limits the applicability of ion beam processing to semiconductor nanostructures. Here, we present an approach that not only avoids this amorphization but in addition allows to tailor the lateral device dimensions of pillars and fins used in modern GAA and Fin-FET designs. Si nanopillars (diameter: 25–50 nm) have been irradiated by either 50 keV broad beam Si + or 25 keV focused Ne + beam from a helium ion microscope (HIM) at various temperatures using fluences of 2×10 16 cm −2 and higher. While at room temperature strong deformation of the nanopillars has been observed, the pillar shape is preserved above 325 ∘ C. This is attributed to ion beam induced amorphization of Si at low temperatures allowing plastic flow due to the ion hammering effect and surface capillary forces. Plastic deformation is suppressed for irradiation at elevated temperatures. Above 325 ∘ C, as confirmed by diffraction contrast in BF-TEM, the nanopillars remain crystalline, and are continuously thinned radially with increasing fluence down to 10 nm. This is due enhanced forward sputtering through the sidewalls of the pillar, and agrees well with 3D ballistic computer simulations. Supported by the H-2020 under Grant Agreement No. 688072.

Si nanopillars of less than 50 nm diameter have been irradiated in a helium ion microscope with a focused Ne+ beam. The morphological changes due to ion beam irradiation at room temperature and elevated temperatures have been studied with the transmission electron microscope. We found that the shape changes of the nanopillars depend on irradiation-induced amorphization and thermally driven dynamic annealing. While at room temperature, the nanopillars evolve to a conical shape due to ion-induced plastic deformation and viscous flow of amorphized Si, simultaneous dynamic annealing during the irradiation at elevated temperatures prevents amorphization which is necessary for the viscous flow. Above the critical temperature of ion-induced amorphization, a steady decrease of the diameter was observed as a result of the dominating forward sputtering process through the nanopillar sidewalls. Under these conditions the nanopillars can be thinned down to a diameter of ∼10 nm in a well-controlled manner. A deeper understanding of the pillar thinning process has been achieved by a comparison of experimental results with 3D computer simulations based on the binary collision approximation.