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Nowadays, “more Moore” and “more than Moore” device architectures are becoming more and more complex. In CEA-Leti, we work on the “CoolCubeTM” 3D sequential integration which is based on the stacking of FDSOI devices [1]. We present solutions, at T Experiments were carried out in an Applied Materials epitaxy reactor featuring (i) liquid precursor delivery, together with H2, N2 or He carrier gas capability, enabling the use of Cl2; (ii) “High Precision Temperature Control (HPTC)”, allowing excellent LT control and enabling flexible rotation speeds; (iii) “precision flow distribution PFD-III”, enhancing uniformity performances. Selective Epitaxial Growth (SEG) is usually obtained with “co-flow” processes at rather high temperatures (>600°C). Chlorinated precursors (SiH2Cl2 (+ GeH4) + HCl, typically) are then sent simultaneously into the growth chamber. At LT ( This strategy allowed us to obtain high quality films, as shown in Fig.1. The Omega-2Theta scans around the (004) X-Ray Diffraction order for tensile SiP (t-SiP) layers grown at T < 500°C with different Phosphorus concentrations were indeed typical of monocrystalline layers, with well-defined and intense peaks together with numerous thickness fringes. The substitutional P contents in those ~ 60 nm thick t-SiP layers were in the 1.02% - 5.42% range. The good layer uniformity in terms of thickness and P content, over a 300mm wafer radius, is shown in figure Fig.2. These layers grown at T Fig.3, with a 0.21 nm Root Mean Square (RMS) roughness for a 60nm thick Si:P layer, i.e. a value close to the typical RMS roughness for t-SiP layers grown at high temperature with a chlorinated chemistry. The electrical resistivity in various t-SiP layers is plotted in Fig.4 as function of the substitutional phosphorus concentration and for various growth temperatures in the 450°C – 525°C range. Reducing the temperature by 75°C halved the electrical resistivity. We were able to achieve a resistivity as low as 0.21 mOhm.cm for a t-SiP layer with 5.8% of P grown at 450°C. We then evaluated, at first on tests structures without gates, our process selectivity. A top view Scanning Electron Microscopy image of a t-SiP layer grown non-selectively, with numerous amorphous SiP nuclei on SiO2, is shown in Fig 5.a. After some careful optimization, we succeeded in having fully selective processes versus SiO2, as shown in Fig 5.b. We then tested such optimized processes on low density FD-SOI devices with 28 nm design rules. A top-view SEM image of transistors after such a growth is shown in Fig.6. The growth selectivity was excellent, with nitride spacers and hard masks as well as isolations free of a-SiP nuclei for 31 nm of t-SiP with 4.5% of P deposited in the Sources/Drains. The surface was smooth, with a RMS roughness as low as 0.30nm on active areas, as shown in Fig.7. Thanks to High Resolution Reciprocal Space Maps (HR-RSM), we measured a Phosphorus concentration of 4.5% for that SiP layer grown on SOI. The very high quality of that epitaxy layer, with well-defined thickness fringes, is obvious in Fig.8. Cross-sectional Transmission Electron Microscopy (TEM) images such as the one shown in Fig. 9 enabled us to confirm, at the nanoscale, the excellent quality of such layers in RSDs. To sum up, we were able to develop a tensile Si:P process which was shown to be selective, at a temperature lower than 500°C, against SiO2 and SiN. Such t-SiP layers were successfully integrated in the Sources/Drains regions of FD-SOI 28nm devices. The very low material resistivity and the high phosphorus content should yield, notably because of tensile strain, performant NMOS devices in the near future. [1] C. Fenouillet-Beranger et al., IEEE TED 68, 3142-3148 (2021) [2] V. Chan et al., IEEE 2005 Custom Integrated Circuits Conference 2005, pp. 667-674 Figure 1

International audience; Dike management has become a major concern in France over the last 20 years, after several major flood disasters caused by river and sea dikes failures. These events, the poor state of more than 60% of the dikes in the country, and the ever-growing threat of floods occurrence increase due to global climate change, have only made obvious the need for dikes reinforcement and for their tighter surveillance. Today, the most commonly used method for both routine and crisis monitoring of dikes is based on visual inspections by field operators. It allows precise detection of most of the surface indicators (i.e animal burrows, structural deformations, topographic anomalies, water seepage, etc.) resulting from disorders affecting these structures. However, this method is time consuming when long sections of dikes are inspected and is not entirely safe for the field operators during a flood. The DIDRO (DIke monitoring by DROnes) project aims at developing a solution for high efficiency routine and crisis monitoring of dikes using a UAV system carrying multiple remote sensing sensors and aquatic measurements equipment. Remote sensing sensors include LiDAR, thermal infrared, near-infrared and visible image sensors, and provide very high resolution data of the surface of the dike. Such very high resolution sensors, which have never been combined so far on a UAV for this type of survey, allow precise detection of a large number of surface indicators of internal and external dike disorders. They can be implemented for both routine and crisis monitoring. Aquatic measurements consist in flow velocity estimations using floating targets dropped in the river or in the sea by the UAV and in a system for water turbidity estimation towed by the UAV. This system is particularly useful for the detection of signs of dike materials erosion during a flood. Also, geophysical methods having proved efficient at providing information on the internal state of dikes, it has been considered very useful to integrate geophysical equipment to the UAV system. Geophysical measurements are conducted using electrical resistivity tomography, self potential and background seismic noise equipment. The UAV is then used to tow or to drop the equipment along the dike and to remotely collect data generated by devices manually positioned. This can be particularly useful during flooding, when accessing the dike may be dangerous. The switch from one payload configuration to another is made easy by a specific mounting system, adaptable to different types of UAV. This makes the DIDRO solution more easily deployable during flooding events. This presentation will focus on the description of the different payload configurations of DIDRO and on the specifications of the equipment used, and will present some results obtained during tests carried out on several dikes in France.

Broad, screening-style assessments of criticality highlight economically important materials facing significant threats to secure, sustainable supply. The studies identify many valuable metrics influencing the likelihood and impact of constraint; however, approaches to aggregating these metrics vary and lack unifying, causally grounded strategies. The present work seeks to advance the state of criticality screening by targeting this gap with structural commodity market insights. Grounded in the principle of price as indicative of economic scarcity, the model uses a small number of high-level metrics to drive changes in future incentive price (i.e., cost of opening new mines) by influencing structural markets elements in different ways (i.e., shape of long-run supply, demand, and incentive curves). Metrics like resource cover, ore grade loss, barriers to entry, secondary supply, end-use substitution and dematerialization rates, and all help to approximate changing supply–demand balance and inform criticality. The approach balances strengths of rapid, broad screening with insights of more detailed market modeling.

Les marchandises coloniales arrivant dans le port nantais n’étaient pas uniquement destinées à la redistribution vers les pays du Nord. Nombre d’entre elles alimentaient un marché de détaillants. Tabac, sucre et indigo se retrouvaient dans les boutiques des apothicaires ou des droguistes nantais. Cette communication montre la diffusion du sucre dans les boutiques nantaises. Le port de Nantes constitue un prisme permettant de saisir la modification des pratiques alimentaires et l’essor de la consommation du sucre.

The natural evolution of rabies virus (RABV) provides a potent example of multiple host shifts and an important opportunity to determine the mechanisms that underpin viral emergence. Using 321 genome sequences spanning an unprecedented diversity of RABV, we compared evolutionary rates and selection pressures in viruses sampled from multiple primary host shifts that occurred on various continents. Two major phylogenetic groups, bat-related RABV and dog-related RABV, experiencing markedly different evolutionary dynamics were identified. While no correlation between time and genetic divergence was found in bat-related RABV, the evolution of dog-related RABV followed a generally clock-like structure, although with a relatively low evolutionary rate. Subsequent molecular clock dating indicated that dog-related RABV likely underwent a rapid global spread following the intensification of intercontinental trade starting in the 15th century. Strikingly, although dog RABV has jumped to various wildlife species from the order Carnivora, we found no clear evidence that these host-jumping events involved adaptive evolution, with RABV instead characterized by strong purifying selection, suggesting that ecological processes also play an important role in shaping patterns of emergence. However, specific amino acid changes were associated with the parallel emergence of RABV in ferret-badgers in Asia, and some host shifts were associated with increases in evolutionary rate, particularly in the ferret-badger and mongoose, implying that changes in host species can have important impacts on evolutionary dynamics., Author Summary Zoonoses account for most recently emerged infectious diseases of humans, although little is known about the evolutionary mechanisms involved in cross-species virus transmission. Understanding the evolutionary patterns and processes that underpin such cross-species transmission is of importance for predicting the spread of zoonotic infections, and hence to their ultimate control. We present a large-scale and detailed reconstruction of the evolutionary history of rabies virus (RABV) in domestic and wildlife animal species. RABV is of particular interest as it is capable of infecting many mammals but, paradoxically, is only maintained in distinct epidemiological cycles associated with animal species from the orders Carnivora and Chiroptera. We show that bat-related RABV and dog-related RABV have experienced very different evolutionary dynamics, and that host jumps are sometimes characterized by significant increases in evolutionary rate. Among Carnivora, the association between RABV and particular host species most likely arose from a combination of the historical human-mediated spread of the virus and jumps into new primary host species. In addition, we show that changes in host species are associated with multiple evolutionary pathways including the occurrence of host-specific parallel evolution. Overall, our data indicate that the establishment of dog-related RABV in new carnivore hosts may only require subtle adaptive evolution.