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In this paper, an overview of today's status and progress, as well as tomorrow's challenges and trends, in the field of advanced nonvolatile memories based on discrete traps is given. In particular, unique features of silicon nanocrystal and SONOS memories will be illustrated through original recent data. The main potentials and main issues of these technologies as candidates to push further the scaling limits of conventional floating-gate Flash devices will be evaluated.

Legionella is able to remain in water as free-living planktonic bacteria or to grow within biofilms that adhere to the pipes. It is also able to enter amoebas or to switch into a viable but not culturable (VBNC) state, which contributes to its resistance to harsh conditions and hinders its detection in water. Factors regulating Legionella growth, such as environmental conditions, type and concentration of available organic and inorganic nutrients, presence of protozoa, spatial location of microorganisms, metal plumbing components, and associated corrosion products are important for Legionella survival and growth. Finally, water treatment and distribution conditions may affect each of these factors. A deeper comprehension of Legionella interactions in water distribution systems with the environmental conditions is needed for better control of the colonization. To this purpose, the implementation of water management plans is the main prevention measure against Legionella. A water management program requires coordination among building managers, health care providers, and Public Health professionals. The review reports a comprehensive view of the state of the art and the promising perspectives of both monitoring and disinfection methods against Legionella in water, focusing on the main current challenges concerning the Public Health sector.

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This work reports on the effect of high temperature annealing on the electrical properties of p-type implanted 4H-SiC. Ion implantations of Aluminium (Al) at different energies (30 -200 keV) were carried out to achieve 300 nm thick acceptor box profiles with a concentration of about 10 20 at/cm 3 . The implanted samples were annealed at high temperatures (1675-1825 °C). Morphological analyses of the annealed samples revealed only a slight increase of the surface roughness RMS up to 1775°C, while this increase becomes more significant at 1825°C (RMS=1.2nm). Room temperature Hall measurements resulted in a hole concentration in the range 0.65-1.34×10 18 /cm 3 and mobility values in the order of 21-27 cm 2 V -1 s -1 . The temperature dependent electrical measurements allowed to estimate an activation energy of the Al-implanted specie of about 110 meV (for the post-implantation annealing at 1675°C) and a fraction of active p-type Al-dopant ranging between 39% and 56%. The results give useful indications for the fabrication of 4H-SiC JBS and MOSFETs.The main dopant species for SiC are Nitrogen (N) and Phosphorous (P) for n-type doping, and Aluminum (Al) for p-type doping. High post-implantation annealing temperatures (> 1500°C) are typically required to bring these species in substitutional positions and achieve their electrical activation [5,6,7]. In particular, selectively doped p-type regions are key parts of both JBS and MOSFETs and the control of their electrical properties has a significant impact on several devices parameters (e.g., Ohmic contacts formation, device on-resistance, threshold voltage and channel mobility, etc.).Hence, understanding the dependence of the properties of p-type implanted layers on the activation annealing temperature is very important for device manufacturers to set the right process for the optimal device characteristics. In this context, although several investigations reported on the properties of Al-implanted 4H-SiC layers [8,9,10], the large variety of experimental conditions and the evolution of the annealing procedures always make this topic open to scientific discussions.Hall-effect measurements are often used to study the electrical properties of p-type 4H-SiC layers, in order to determine key parameters like the holes concentration and mobility [11]. A critical issue of this methodology is the choice of the Hall scattering factor rH for SiC [12,13]. In fact, the difficulty to extract the mobility and the free hole concentration from Hall measurements is related to the correct knowledge of rH. However, many authors often interpret the experimental Hall results on p-type 4H-SiC assuming rH=1, which in turn leads to an overestimation of the doping level in the material [9,14]. Only few works specifically reported experimental calculations of the Hall scattering factor rH for SiC [15,16], whose findings should be considered for a correct analysis of the currently available data.This paper reports on the morphological and electrical properties of p-type implanted 4H-SiC annealed...

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Inorganic mercury (Hg2+) pollution of water reserves, especially drinking water, is an important issue in the environmental and public health field. Mercury is reported to be one of the most dangerous elements in nature since its accumulation and ingestion can lead to a series of permanent human diseases, affecting the kidneys and central nervous system. All the conventional approaches for assaying Hg2+ have some limitations in terms of bulky instruments and the cost and time required for the analysis. Here, we describe a miniaturizable and high-throughput bioluminescence sensor for Hg2+ detection in water, which combines the specificity of a living bacterial Hg2+ reporter cell, used as sensing element, with the performance of a silicon photomultiplier, used as optical detector. The proposed system paves the basis for portable analysis and low reactants consumption. The aim of the work is to propose a sensing strategy for total inorganic mercury evaluation in water. The proposed system can lay the basis for further studies and validations in order to develop rapid and portable technology that can be used in situ providing remote monitoring.

This paper reports on the electrical activation and Ohmic contact properties on p-type Al-implanted silicon carbide (4H-SiC). In particular, the contacts were formed on 4H-SiC-implanted layers, subjected to three different post-implantation annealing processes, at 1675 °C, 1175 °C, and 1825 °C. Under these post-implantation annealing conditions, the electrical activation of the Al dopant species increased from 39% to 56%. The Ti/Al/Ni contacts showed an Ohmic behavior after annealing at 950 °C. The specific contact resistance ρc could be lowered by a factor of 2.6 with the increase of the post-implantation annealing temperature. The result can be useful for application in device fabrication. Moreover, the dependence of ρc on the active acceptor concentration followed the thermionic field emission model, with a barrier height of 0.63 eV.