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In recent years, several new applications of SiC (both 4H and 3C polytypes) have been proposed in different papers. In this review, several of these emerging applications have been reported to show the development status, the main problems to be solved and the outlooks for these new devices. The use of SiC for high temperature applications in space, high temperature CMOS, high radiation hard detectors, new optical devices, high frequency MEMS, new devices with integrated 2D materials and biosensors have been extensively reviewed in this paper. The development of these new applications, at least for the 4H-SiC ones, has been favored by the strong improvement in SiC technology and in the material quality and price, due to the increasing market for power devices. However, at the same time, these new applications need the development of new processes and the improvement of material properties (high temperature packages, channel mobility and threshold voltage instability improvement, thick epitaxial layers, low defects, long carrier lifetime, low epitaxial doping). Instead, in the case of 3C-SiC applications, several new projects have developed material processes to obtain more performing MEMS, photonics and biomedical devices. Despite the good performance of these devices and the potential market, the further development of the material and of the specific processes and the lack of several SiC foundries for these applications are limiting further development in these fields.

In this work, we investigate, by μ-Raman spectroscopy the distribution of stress field on a micro-machined structures. They were realized on a 3C-SiC substrate, grown on a Silicon On Insulator (SOI) wafer, after lithography and etching processes. Various structures, such as strain gauge, single and double clamped beams, were analyzed, showing different stress distributions. All the structures show an intense variation of stress close to the undercut region.

Presentation done atWOCSDICE - EXMATEC 2023 - Palermo.&nbsp

Poster presented at the 2021 European Conference on Silicon Carbide and Related Materials(ECSCRM).

We report the use of an electrostatic MEMS-based device to produce high quality electron vortex beams with more than 1000 quanta of orbital angular momentum (OAM). Diffraction and off-axis electron holography experiments are used to show that the diameter of the vortex in the diffraction plane increases linearly with OAM, thereby allowing the angular momentum content of the vortex to be calibrated. The realization of electron vortex beams with even larger values of OAM is currently limited by the breakdown voltage of the device. Potential solutions to overcome this problem are discussed.

MEMS based electron optics are a promising approach for a new generation of experiments in electron microscopy. In this contribution we improve analytically the modelling of the MEMS based phase plates with thin electrodes with accurate account of the fringing fields. As a result we are able to improve the design and the boundary conditions in MEMS-based spiral phase plates acting on the control parameters. We checked the quality of the generated vortex beam.

This deliverable is meant to summarise the final results regarding the plasmon analysis based on OAM sorter. The aim is to prove that we can achieve a substantial scientific advancement using the OAM-sorter that was not possible without it. We document here both the actual scientific results and the partial attempts that could not be brought to conclusions. The deliverable is separated into 2 main chapters. Chapter 1 reports the efforts to produce the Q-SORT setup for different kinds of plasmon observation and explains why the setup has to be different for every specific experiment. Chapter 2 reports the actual scientific results, of high fundamental relevance, that we obtained for volume plasmons. The experimental results are qualitatively and quantitatively compared with simulation. Conclusions are drawn at the end. It is worth highlighting here that the OAM sorter allowed us to better understand the characteristics of plasmon loss excitation and to find a new phenomenon consisting of the ‘spontaneous Emission’ of quanta of OAM in the interaction with plasmon. Surprising theoretical results were also obtained thanks to the definition of coherence through innovative density matrix formalism: we showed that the coherence of the initial OAM state superposition of the electron is partially preserved after the electron-plasmon scattering, which is reflected mathematically by the possibility of expressing the post-scattering electron density matrix as the sum of one fully coherent term containing the initial OAM values and another term which is characterised by full OAM decoherence. The theory was confirmed by experiment in this case as well.

This deliverable reports the comprehensive results and activities aimed to demonstrate Electron Magnetic Circular Dichroism (EMCD). It is difficult to keep the delicate OAM sorter alignment at the large energy-loss of the iron L-edge (about 700 eV). Considering also the slowdowns due to COVID-19 pandemic we opted for an equally and similar problem by looking at the difference in the σ* and π* transition in 2D material in the energy range of 200eV energy loss. The kind of information and the OAM–EELS theory is fundamentally the same as real EMCD but the difficulty in the alignment is reduced. The experiment therefore succeeds in demonstrating the importance of the combination of OAM-EELS experiment also to study atomic transitions. Considering the similarities of the two experiments this work demonstrate that EMCD is feasible and that automatic alignment procedure should soon allow to explore the energy loss range of EMCD. For these reasons, most of this work will be of quite general interest and only a small part will regard the case of h-BN. Given the rising importance of 2D material that are now receiving even more attention than magnetic structure the result has also a large importance in its own right and fully demonstrates the potentialities of a OAM sorter in material science. Chapter 1 will explain all the improvements we carried out in the direction of EMCD and in OAM–EELS experiments. A large space has been dedicated to the automatic control of the microscope by means of a neural network. Given the difficulties to control the many parameters, this will probably be the best way to carry out the most difficult future experiments. Chapter 2 will explain all problems of localization and decoherence. Once again this theoretical framework is valid for all OAM–EELS experiments and is of general interest to understand our data and to design future experiments. Chapter 3 is dedicated to effective manuscript draft with experiments and data analysis. As for the setup also the deconvolution method used in this section can be easily transported to the case of EMCD.

In quantum mechanics, each conserved quantity (e.g., energy, position, linear momentum and angular momentum) is associated with a Hermitian operator. Its expected value can then be determined by performing a measurement on the wavefunction. In modern electron microscopy, one can select the initial and final states of the electron and the measurement basis by performing measurements of scattering processes. For example, the orbital angular momentum (OAM) of an electron can be used to reveal the n-fold symmetry of a wavefunction scattered by a sample. Here, we introduce a new composite planar chirality operator that can be used to measure a spiral-like feature in a sample. This concept develops the concept of chirality to highlight a specific roto-scale symmetry. We show that planar chirality can be characterized using an electron OAM sorter to uncover the atomic structures of biomolecules in cryo electron microscopy, either in a stand-alone analysis for fast identification of protein structures or in the context of conventional cryo electron microscopy to produce faster and more detailed 3D reconstructions by solving upside-down orientation ambiguities., available also at arXiv:2110.03391 This project has received fundings also from the Deutsche Forschungsgemeinschaft (Project-ID 405553726 – TRR 270), from the DARPA TEE program (Grant MIPR# HR0011831554) and from an Ontario Early Researcher Award (ERA) and a Canada Research Chair (CRC).

3C-SiC is an emerging material for MEMS systems thanks to its outstanding mechanical properties (high Young’s modulus and low density) that allow the device to be operated for a given geometry at higher frequency. The mechanical properties of this material depend strongly on the material quality, the defect density, and the stress. For this reason, the use of SiC in Si-based microelectromechanical system (MEMS) fabrication techniques has been very limited. In this work, the complete characterization of Young’s modulus and residual stress of monocrystalline 3C-SiC layers with different doping types grown on &lt, 100&gt, and &lt, 111&gt, oriented silicon substrates is reported, using a combination of resonance frequency of double clamped beams and strain gauge. In this way, both the residual stress and the residual strain can be measured independently, and Young’s modulus can be obtained by Hooke’s law. From these measurements, it has been observed that Young’s modulus depends on the thickness of the layer, the orientation, the doping, and the stress. Very good values of Young’s modulus were obtained in this work, even for very thin layers (thinner than 1 mm), and this can give the opportunity to realize very sensitive strain sensors.

3C-SiC is an emerging material for MEMS systems thanks to its outstanding mechanical properties (high Young’s modulus and low density) that allow the device to be operated for a given geometry at higher frequency. The mechanical properties of this material depend strongly on the material quality, the defect density, and the stress. For this reason, the use of SiC in Si-based microelectromechanical system (MEMS) fabrication techniques has been very limited. In this work, the complete characterization of Young’s modulus and residual stress of monocrystalline 3C-SiC layers with different doping types grown on and oriented silicon substrates is reported, using a combination of resonance frequency of double clamped beams and strain gauge. In this way, both the residual stress and the residual strain can be measured independently, and Young’s modulus can be obtained by Hooke’s law. From these measurements, it has been observed that Young’s modulus depends on the thickness of the layer, the orientation, the doping, and the stress. Very good values of Young’s modulus were obtained in this work, even for very thin layers (thinner than 1 μm), and this can give the opportunity to realize very sensitive strain sensors.

This deliverable reports on the progress that has been achieved in the direction of the dose-effective imaging of organic molecules. We report several essential experimental advancements, including a successful experimental scheme of ghost imaging that could be realised in Modena without the need of travelling. Overall this deliverable includes material for at least 3 papers and a patent. The restriction on travels due to Covid-19 imposed hard constraints on the performance of the intended experiment. The complete experiment on proteins would, in fact, have required the simultaneous presence of three groups at the microscope in Jülich: FZJ personnel for main operation on the microscope, people from MU for the cryomicroscopy part, and people from CNR for the lateral control of software and for the coordination of the experiment. Moreover, the preparation of the experiment required the intervention of FEI personnel. Unfortunately, in spite of the partial release of the restrictions during the extra 6 months allotted to Q-SORT, for the reasons given above these conditions were impossible to meet. This was unforeseeable at the moment the project extension was asked. Given these hard constraints, we chose the combination of experimental activities that allowed us to achieve the greatest possible amount of project goals. In fact, Q-SORT scientists achieved more than what was foreseen; novel results include: 1) the first patentable phase plates of different design ( designed in WP3 D3.4 for protein recognition) able to control up to 24 electrodes by multiplexing the initial 8 inputs. 2) the first computational ghost imaging experiment in microscopy and its optimization for low dose regime 3) a state of the art neural network control for an efficient prediction of the generated caustic pattern. Two approaches to the protein recognition were chosen at the end of WP3: a) the extension of the OAM sorter with an additional programmable phase plate. Such approach is referred to as GOAMS (generalised OAM sorter) in D3.2 as b) the computational ghost imaging with increasingly complex masks. Under the given constraints, it was found that the computational ghost imaging approach (D3.2, task 3.1 & 3.2) was the most appropriate and effective to pursue - enabling the greatest advancement. This development is also consistent with contingency plan #6 “Test random or Hadamard sparse sampling”. The results have been also written as a manuscript that is going to be submitted soon. The hardware for the 3-element GOAMS (i.e. the second approach that was found to be most promising in WP3) was also developed, with the design of an additional element that allowed the recognition of the radial degree of freedom. Such extended “protein specific” phase modulator (D3.4) was also finished and tested as one of the design of the programmable phase plates. [...]

The aim of this task was to report about the development toward electrostatic elements for the realization of an Orbital Angular Momentum sorter. We study in particular the parametric dependence on the fabrication and operation details and see a) if the present solution could produce a working sorter b) which improvements are necessary for the final version of the sorter. The outcomes of this deliverable are strongly related to the realization of deliverable 2.6 “Manuscript for paper on implementation of new phase elements in TEM” which in turn is propaedeutic to the whole WP4 for material science applications and to D5.4 in WP 5.

This deliverable is the final result of WP2 marking the realization of a working sorter device. The completion of this device marks the realization of Milestone M6 and the progress in the realization of WP4 and part of WP5. The deliverable is written in the form of paper describing the main results. The main part of the text of the paper is divided in Introduction, Experimental setup, Sorter in practice, results, Effect of the astigmatism correction electrodes, Phase of sorter 2, conclusions. The main aim of the first 3 sections is to explain the setup of the sorter and its working mode. The second part is instead concentrated on what can be still improved or anyway important details that really matter for the final resolution of the device. In addition we added a large supplementary section partially copied by the previous deliverable. This material would be strongly necessary as the paper is now very technical Finally we added the comment of two internal reviewer and our response to that.

This deliverable contains the first conclusions about the viability of electron magnetic chiral dichroism (EMCD) experiments, as the acquisition of atomic-scale EMCD is one of the main goals of the Project. In preparation for the actual EMCD measurement, a large comprehensive theoretical and experimental-test work was found out to be necessary. Such work focused on both the modified electron optics as well as on the interaction between probe electrons and sample and is described in this deliverable.

This paper presents an ultra-low power, silicon-integrated readout for resonant MEMS strain sensors. The analogue readout implements a negative-resistance amplifier based on first-generation current conveyors (CCI) that, thanks to the reduced number of active elements, targets both low-power and low-noise. A prototype of the circuit was implemented in a 0.18-µm technology occupying less than 0.4 mm2 and consuming only 9 µA from the 1.8-V power supply. The prototype was earliest tested by connecting it to a resonant MEMS strain resonator.