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Describing the time evolution of Plasma Facing Materials (PFMs), through quantitative evaluations of erosion, roughness, and physical properties degradation, is one of the difficult challenges to reach the goal of efficient energy production by nuclear fusion. To follow all the aging-connected physical and chemical phenomena through their characteristic dimensional scale, and to estimate the PFM microstructural transformation over time, we propose a predictive sequential multiscale methodology, consisting of two database-provided coupled codes. The first is a time-dependent, volume-averaged, plasma simulator which describes completely this system in terms of thermodynamics, composition and evaluation of the sheath potential. Plasma solutions are geometrically rearranged by adding surface reactions and 3D geometric features. To increase sensitivity, plasma information is provided to the second code as an initial condition. Such a code is a 3D kinetic Monte Carlo in-cell algorithm for the nano-scale erosion simulation describing the PFM interactions through an extendable set of physical phenomena, such as sticking, sputtering, ion enhanced removals and ion penetration. In this paper, we perform simulations for the case of study of Hydrogen (H) plasmas produced in linear devices, reaching the quasi-atomic detail of the plasma induced material modification of tungsten (W) as PFM.

A new carbon nanotube-based device for detection of Arginase 1 (ARG-1) was produced. Multi-walled carbon nanotubes (MWCNTs) were deposited between electrodes by dielectrophoresis (DEP) in an accurate and reproducible way. This deposition method has the advantages of low cost and room temperature conditions and therefore, can be used on different kinds of substrates (silicon, glass, plastics) allowing for large scale production of chemical or biological sensors. Scanning electrical microscope (SEM) and electrical characterization have been performed on the biosensors before and after protein exposure. The devices were tested in the present work for the detection of ARG-1. They show high sensitivity and reproducibility, and can be easily and suitably modified to detect other proteins. Keywords: Carbon nanotube, Biosensor, Arginase, Dielectrophoresis, Biomarker, Protein

Laser Thermal Annealing (LTA) at various energy densities was used to recrystallize and activate amorphized germanium doped with phosphorous by ion implantation. The structural modifications induced during the recrystallization and the related dopant diffusion were first investigated. After LTA at low energy densities, the P electrical activation was poor while the dopant distribution was mainly localized in the polycrystalline Ge resulting from the anneal. Conversely, full dopant activation (up to 1 × 1020 cm−3) in a perfectly recrystallized material was observed after annealing at higher energy densities. Measurements of lattice parameters performed on the fully activated structures show that P doping results in a lattice expansion, with a perpendicular lattice strain per atom βPs = +0.7 ± 0.1 Å3. This clearly indicates that, despite the small atomic radius of P compared to Ge, the “electronic contribution” to the lattice parameter modification (due to the increased hydrostatic deformation potential in the conduction band of P doped Ge) is larger than the “size mismatch contribution” associated with the atomic radii. Such behavior, predicted by theory, is observed experimentally for the first time, thanks to the high sensitivity of the measurement techniques used in this work.

In this work we report on the development of back-gated carbon nanotube-field effect transistors (CNT-FETs), with CNT layers playing the role of the channel, and on their electrical characterisation for sensing applications. The CNTs have been deposited by electrophoresis on an interdigitated electrode region created on a SiO2/Si substrate. Different kinds of CNTs have been used (MWCNTs by arc discharge in liquid nitrogen and MWCNTs by chemical vapour deposition, CVD) and the electrical characterisation of the devices was performed in a NH3- and NO2-controlled environment. Preliminary data have shown an increase in the channel resistance under NH3 exposure, whereas a decrease is observed after exposure to NO2, and the sensitivity to each gas depends on the kind of CNTs used for the device. Furthermore, the defect formation by Si ion implantation on CNTs was investigated by high-resolution transmission electron microscopy (TEM) and Raman analysis. The behaviour observed for the different devices can be explained in terms of the interaction between structural or chemical defects in CNTs and the gas molecules.

The 11th Italian Quantum Information Science conference (IQIS 2018) took place in Catania, Italy, at the Monastero dei Benedettini, from September 17 to 20, 2018. IQIS 2018 was organized by the Department of Physics and Astronomy “E. Majorana” of the University of Catania, and by IMM-CNR, Catania. The conference also hosted an event dedicated to the FET-Flagship 2018/28 on Quantum Technologies. These proceedings collect papers contributed by the participants, which extend presentations delivered at the conference, and were subjected to peer-reviewing. They provide a snapshot of the contributions (mainly, but only) by the Italian scientific community to the developing field of quantum information and related subjects.

Ultraviolet nanosecond laser annealing (UV‐NLA) proves to be an important technique, particularly when tightly controlled heating and melting are necessary. In the realm of semiconductor technologies, the significance of NLA grows in tandem with the escalating intricacy of integration schemes in nanoscaled devices. Silicon–germanium alloys are studied for decades for their compatibility with silicon devices. Indeed, they enable the manipulation of properties like strain, carrier mobilities, and bandgap. In this framework, they can for instance boost the performances of p‐type MOSFETs but also enable near infrared absorption and emission for applications in photodetection and photonics. Laser melting on such types of layers, however, results, up to now, in the development of extended defects and poor control over layer morphology and homogeneity. Herein, the laser melting of ≈700 nm‐thick relaxed silicon–germanium samples coated with SiO2 nanoarrays, observing the resulting material to maintain an unaltered lattice, is investigated. It is found that the geometrical parameters of the silicon oxide have an impact on the thermal budget samples, influencing melt threshold, melt depth, and germanium distribution. [ABSTRACT FROM AUTHOR]

Low-Gain Avalanche Diodes (LGADs) are critical sensors for the ATLAS and CMS timing detectors at the High Luminosity Large Hadron Collider (HL-LHC), offering enhanced timing resolution with gain factors of 20 to 50. However, their radiation tolerance is hindered by the Acceptor Removal Phenomenon (ARP), which deactivates boron in the gain layer, reducing gain below the threshold for accurate timing. This study investigates the radiation hardness of thin, carbon-doped LGAD sensors developed by Brookhaven National Laboratory (BNL) to address ARP-induced limitations. Active dopant profiles in the gain layer, junction, and bulk were measured using a Spreading Resistance Probe (SRP) profilometer, and the effects of annealing and neutron irradiation at fluences of 3 × 1014, 1 × 1015, and 3 × 1015 neq/cm2 (1 MeV equivalent) were analyzed. Low carbon dose rates showed minimal improvement due to enhanced deactivation, while higher doses improved radiation hardness, demonstrating a non-linear dose–response relationship. These findings highlight the potential of optimizing gain layers with high carbon doses and low-diffusion boron to extend LGAD lifetimes in high-radiation environments. Future research will refine carbon implantation strategies and explore alternative approaches to further enhance the radiation hardness of LGADs. [ABSTRACT FROM AUTHOR]

Silicon nanowires (SiNWs) are extensively studied in the scientific community due to their remarkable electrical and optical properties. In our previous studies, we have demonstrated that cylindrical−shaped SiNWs sustain longitudinal plasmon resonances (LPRs) and transverse plasmon resonances (TPRs). In this work, we will present the results of our investigation on conical SiNWs with different lengths and demonstrate that the NW size plays a role on the spectral response. We selected two groups of SiNWs with approximately 300 nm and 750 nm in length with different lengths and diameters. We investigated the optical properties of the SiNWs at a high energy and spatial resolution by using transmission electron microscopy and in situ electron energy loss spectroscopy. In the UV region of the spectrum investigated here, the experimental evidence suggests the presence of LPRs and a clear presence of TPRs. We found that, as the NW length increases, the LPR fundamental mode shifts towards higher energies, while the diameter seems to affect the TPR, shifting it to lower energy levels when the diameter increases. These SiNWs can play a role in the development of low−dimensional devices for applications in nano−electronics and nano−photonics. [ABSTRACT FROM AUTHOR]

Al 2 O 3 /AlGaN metal-oxide-semiconductor capacitors show a hysteretic behavior in their capacitance vs voltage characteristics, often attributed to near-interface traps deriving from defects within the oxide layer. The origin as well as the structural/electronic properties of such defects are still strongly debated in the literature. Here, we use ab initio molecular dynamics and the climbing-image nudged elastic band method to show that aluminum Frenkel defects give rise to bistable trap states in disordered and stoichiometric Al 2 O 3. Based on these results, we propose a calibrated polaron model representing a distribution of individually interacting energy levels with an internal reconfiguration mode and coupled to continuous bands of carriers to explain the hysteresis mechanism in Al 2 O 3 /AlGaN capacitors. [ABSTRACT FROM AUTHOR]

In this study, the optical behavior of lead‐free Bi‐based low‐dimensional perovskite single crystals (Cs3Bi2Cl9, Cs3Bi2Br9, Cs3Bi2I9, and MA3Bi2I9) is investigated by spectroscopic ellipsometry, supported by X‐ray diffraction and density functional theory calculations. All materials exhibit a strong excitonic peak resulting from photogenerated electron–hole Coulomb interactions, whereas the threshold of continuous absorption is found at higher energies. The resonances of the excitonic and continuous bands, along with exciton binding energies, are extracted through Critical Point Analysis of the ellipsometric data over a wide temperature range (from −90 °C to 90 °C), revealing subtle variations in the optical characteristics for each single crystal. These materials can be applied in optoelectronics as photodetectors because of their high stability and lower toxicity compared to their Pb‐based perovskites. [ABSTRACT FROM AUTHOR]

Hole‐transporting layer‐free mesoporous carbon (mC) architectures represent a printable, low‐cost, and stable solution for the future commercialization of perovskite solar cells (PSCs). CsPbI3 perovskite is attracting attention for its inorganic structure, which yields higher structural stability compared to hybrid counterparts and allows reversibility of its photoactive phase. Here the photovoltaic performance of large‐area (144 mm2) devices infiltrated with CsPbI3:EuCl3 is systematically evaluated, using AVA‐MAPbI3 mC‐PSCs as a reference. Measured and simulated J–V curves acquired at various scan rates show a significantly reduced hysteresis for Eu‐doped CsPbI3 with respect to AVA‐MAPbI3 mC‐PSCs. The synergic comparison between experiments and simulations reveals the complex interplay between ionic and electronic charges in the two mC‐PSCs, supporting the argument that cation migration is suppressed in CsPbI3:EuCl3. This also agrees with steady‐state photoconversion efficiency measured and simulated at fixed bias, which is constant over time in CsPbI3:EuCl3, contrary to what occurs in AVA‐MAPbI3 where a decay arises from enhanced ionic migration. In addition, CsPbI3:EuCl3 mC‐PSCs maintain their initial efficiency up to 250 h at 55 °C under continuous illumination during maximum power point tracking measurements. The possibility of reusing the CsPbI3:EuCl3 mC‐PSCs multiple times is demonstrated, pointing out the superiority of this inorganic perovskite in terms of sustainability. [ABSTRACT FROM AUTHOR]

We investigate the microstructural evolution of electrochemically deposited poly-crystalline Cu films during subsequent thermal process cycles at mild maximum temperatures, compatible with the integration in advanced metallization schemes for electronic device manufacturing. The modifications induced by the thermal budget have been characterized at different scales (from the film-substrate interface to the wafer scale) with different complementary techniques: X-ray Diffraction (XRD), scanning electron microscopy (SEM), atomic force microscopy (AFM), and dynamical warpage measurements. Moreover, the film internal grains' evolution has been modelled by a tri-dimensional on-cell model, derived by the Pott-like multi-states configurational energy dependence, able to consider multiple orientation of the grains and densification kinetics in the canonical ensemble. Finally, a macroscopic model of the warpage dependence on the process conditions is discussed. The presented joint theoretical and experimental analysis provides a complete and consistent scenario of the grain densification phenomenon and its impact for the Cu film microstructure and the composite system morphology, indicating several strategies for the integration of the process in real device structures. [ABSTRACT FROM AUTHOR]

The combination of the unique physical properties of molybdenum disulfide (MoS2) with those of gallium nitride (GaN) and related group-III nitride semiconductors have recently attracted increasing scientific interest for the realization of innovative electronic and optoelectronic devices. A deep understanding of MoS2/GaN interface properties represents the key to properly tailor the electronic and optical behavior of devices based on this heterostructure. In this study, monolayer (1L) MoS2 was grown on GaN-on-sapphire substrates by chemical vapor deposition (CVD) at 700 °C. The structural, chemical, vibrational, and light emission properties of the MoS2/GaN heterostructure were investigated in detail by the combination of microscopic/spectroscopic techniques and ab initio calculations. XPS analyses on as-grown samples showed the formation of stoichiometric MoS2. According to micro-Raman spectroscopy, monolayer MoS2 domains on GaN exhibit an average n-type doping of (0.11 ± 0.12) × 1013 cm−2 and a small tensile strain (ε ≈ 0.25%), whereas an intense light emission at 1.87 eV was revealed by PL analyses. Furthermore, a gap at the interface was shown by cross-sectional TEM analysis, confirming the van der Waals (vdW) bond between MoS2 and GaN. Finally, density functional theory (DFT) calculations of the heterostructure were carried out, considering three different configurations of the interface, i.e., (i) an ideal Ga-terminated GaN surface, (ii) the passivation of Ga surface by a monolayer of oxygen (O), and (iii) the presence of an ultrathin Ga2O3 layer. This latter model predicts the formation of a vdW interface and a strong n-type doping of MoS2, in closer agreement with the experimental observations. [ABSTRACT FROM AUTHOR]

In this study, we explore the potential of a blended material comprising CsPbI 3 : EuCl 3 perovskite and Gig-Lox TiO 2 , a unique transparent spongy material known for its multi-branched porous structure, for application in solar cells. The inclusion of EuCl 3 in CsPbI 3 serves to stabilize the photoactive γ -phase with a bandgap of 1.75 eV, making it suitable for solar energy conversion in tandem solar cells. Our study applies X-ray-based techniques to investigate the structural properties and interfacial behavior within this blended material, in comparison with a reference perovskite layer deposited on glass. In addition, Spectroscopic ellipsometry is complemented with density functional theory calculations and photoluminescence measurements to elucidate the absorption and radiative emission properties of the blend. Notably, our findings reveal a significant quenching of photoluminescence within the blended material, underscoring the pivotal role of the distributed interfaces in facilitating efficient carrier injection from the CsPbI 3 : EuCl 3 perovskite into the Gig-Lox TiO 2 sponge. These findings pave the way for the application of the blend as an Electron Transport Layer (ETL) in semi-transparent perovskite solar cells for tandem and building integrated photovoltaics. [ABSTRACT FROM AUTHOR]