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Atom probe tomography was employed to observe and derive the composition of carbon clusters in implanted silicon. This value, which is of interest to the microelectronic industry when considering ion implantation defects, was estimated not to exceed 2 at%. This measurement has been done by fitting the distribution of first nearest neighbor distances between monoatomic carbon ions (C+ and C2+). Carbon quantification has been considerably improved through the detection of molecular ions, using lower electric field conditions as well as equal proportions of 12C and 13C. In these conditions and using another quantification method, we have shown that the carbon content in clusters approaches 50 at%. This result very likely indicates that clusters are nuclei of the SiC phase.

Carbon has been co-implanted to phosphorus at low temperature (−100 °C) in silicon. As compared to a room temperature carbon implant, phosphorus activation is increased due to the suppression of extended defects. The unusual carbon depleted region observed in both secondary ion mass spectroscopy and atom probe tomography annealed profiles has been explained and modeled using an interstitialcy diffusion barrier of 0.6 eV. Carbon clusters have been interpreted as being composed of several immobile dimers carbon/self-interstitial, in agreement with the stoichiometry of the SiC phase. From the model presented here, an adequate temperature window (>750 °C) has been found regarding self-interstitials trapping by carbon.

Atom Probe Tomography (APT) was used to quantify carbon in implanted silicon at two various electric fields (~ 15 and 20 V/nm). Using equal proportions of implanted 12C and 13C, the numerous molecular ions that were observed were identified and their contribution to the carbon content statistically derived. Much more accurate carbon quantification was obtained in the lowest electric field analysis by comparing APT with Secondary Ion Mass Spectroscopy profiles. This was assigned to a lower amount of molecular ion dissociations. Furthermore, the number of self-interstitials trapped per carbon atom in clusters was derived. This value of interest for the microelectronics industry regarding dopant diffusion and implantation induced defects was estimated close to one, in agreement with the expected stoichiometry of the SiC phase present in the phase diagram. However, this was obtained only when using low electric field conditions.

While 5G wireless networks are currently deployed around the world, preliminary research activities have begun to look beyond 5G and conceptualize 6G standard. Although it is envisioned that 6G may bring an unprecedent transformation of the wireless networks in comparison with previous generations, the necessity to develop analog and RF specialized technologies to address new frequency spectra will remain. In this paper, we review the development of PD-SOI CMOS and SiGe BiCMOS technologies addressing 5G RF Integrated Circuits (RFICs) and their evolutions for 6G.

Dopant diffusion and structural defects are investigated in a carbon-phosphorus implanted silicon. End-of-range defects maturation and phosphorus diffusion are inhibited. A direct imaging of carbon segregation to dislocation loops is given by atom probe tomography. Segregation energies of carbon atoms to these defects are estimated to be about 0.37 eV. The comparison between observed and derived cluster radii indicates a quick decrease in the self-interstitial supersaturation during the nucleation step of carbon precipitation. Carbon clusters are likely to be the precursors of a metastable phase, which is not the expected SiC phase.

Until the 90-nm node, CoSi 2 silicide have been widely used in semiconductor industry. More recently, in order to meet performance requirements in advanced digital nodes, process integration have consensually shifted towards NiPt-based silicides [1] . Nevertheless, advanced memory and imaging technologies being still based on 90-nm core MOS, developments and studies on CoSi 2 silicide are still of the best interest as new challenges are emerging.

This paper deals with the optimization of a Si/SiGe HBT featuring an implanted collector and a DPSA-SEG emitter-base architecture. Arsenic and phosphorous doping species are studied. On the one hand, both silicon defects and dopants profiles control are evaluated and on the other hand, hf performances are presented. Carbon-phosphorous co-implantation is also investigated and a state-of-the-art 450 GHz $f_{\text{T}}$ HBT compatible with 55-nm MOSFETs is demonstrated through a device layout study.

International audience; We present experimental and simulated J-V characteristics of Metal/Insulator/Semiconductor (MIS) junctions aiming at improving the contact resistivity for advanced CMOS nodes. We show that an Atomic Layer Deposition (ALD)-based Al2O3 process may induce a native silicon oxide regrowth leading to an additional tunneling resistance in series. A modelling-based analysis of Metal/Insulator/Insulator/Metal (MIIS) contacts, including the potentially beneficial interfacial dipole, provides a new outlook on high-kappa/SiO2 bilayers for low resistivity contacts.

In order to obtain information about different factors which exert a great influence on the conformational equilibria of mono-, di- and oligonucleotides, the average conformation of four heterodinucleoside monophosphates, ApC, CpA, ApU and UpA, was studied by 1H-NMR at 250 MHz and compared with that of GpC, CpG, GpU, UpG and the corresponding nucleosides and nucleotides. The ratio of N S conformers and the rotamer distribution of the exocyclic group were evaluated from proton-proton coupling constants, and the orientation of the base about the glycosidic bond from proton relaxation involving selective deuteration. The influence of intra- and intermolecular interactions on proton chemical shifts and conformational equilibria has been carefully studied from temperature and concentration effects. The results show that intermolecular base-base stacking does not modify the average conformation of dinucleoside monophosphates, while the intramolecular interaction (between residues of the same molecule) favours the N conformer, the gg rotamer and the anti conformation. The large upfield shift of H5′ (lower field resonances) compared with H5″ (higher field resonances) and the large variation of the N proportion with increasing temperature suggest that H3′ is statistically closer to H5′ than H5″. There is a correlation between temperature, the gg rotamer and the variation in the relative chemical shifts between H5′ and H5″. These conclusions are in agreement with those of our previous work on GMPs using pH and temperature effects. T1 relaxation studies indicate a large predominance of the anti conformation for both residues of ApC and ApU; these two compounds also exhibit a very high degree of association. For the naturally occurring ribonucleoside derivatives in aqueous solution, the base chemical structure, the position of the phosphate group, the temperature and pH are among the most important factors which can modify the conformation equilibria of molecules: the N conformation is generally more favoured in pyrimidine than in purine derivatives. The anti proportion is higher in 5′- than in 2′- or 3′-mononucleotides. However, the influence due to the position of the phosphate group is not determined in dinucleoside monophosphates. The temperature effect is negligible on the conformation of monomers but is remarkably large for the dimers: it consists of reducing the N and gg proportions which are preponderant in the dimers at room temperature. The pH effect is particularly large for the G residue, the conformation of which changes upon pr tonation at N7 (pK ≈ 2.3); the N conformer is favoured at acidic pH.

The configuration and the conformation of alpha and beta anomers of pyrazomycin, cytidine and pseudouridine in aqueous solution have been investigated by 1H-NMR at 250 MHz. T1 proton relaxation measurements are an excellent method to determine the conformation of the base around the glycosidic linkage. Frequently, steric hindrance considerations can help to decide which conformations are possible in nucleoside anomer pairs. The proton-proton coupling constants indicate that the N conformer is largely predominant in the alpha anomers while the S conformer is particularly abundant in beta-pyrazomycin. The steric hindrance is much larger for alpha than for beta-nucleosides and change of a C-C to a C-N glycosidic bond reduces considerably the rotational possibilities of the base. The relaxation data show that alpha-cytidine adopts the anti conformation with gamma = 200 degrees in good agreement with the crystal structure and with the sterical computations. In the other case, when the syn and anti conformations are sterically accessible, the orientation of the base may be completely different from one nucleoside to the other. It can be predicted neither from the crystal structure nor from comparisons with similar compounds. For alpha-pseudo-uridine the predominant orientation of the base (gamma = 120 degrees) is in the boundary of the syn-anti regions; for beta-cytidine the syn (gamma = 65 degrees) and anti (gamma = 215 degrees) conformations are equiprobable at room temperature while beta-pseudouridine shows the syn conformation with gamma = 40 degrees, the smallest angle observed until now. There is no correlation between the N/S and syn-anti ratios.

An original design for a cooled exchangeable polychromator for energy-dispersive XAFS (X-ray absorption fine structure) working either in the transmission configuration (Laue case) or in the reflection configuration (Bragg case) is presented. It enables the acquisition of X-ray absorption spectra between 5 and 25 keV with a spot size on the sample that can reach to less than 20 microm FWHM for some energies. Only 1 h is needed to exchange both benders in operative mode. Parallel transmission spectra with a bandpass between 5 and 10% can be obtained in the full energy range. The dispersive optics and mechanics of ID24 (ESRF, Grenoble, France) have been designed to obtain XAFS spectra in less than 1 s and, in some cases, in the millisecond range.