Simulation study for the CDM ESD behaviour of the grounded-gate nmos

The parasitic bipolar transistor inherent to grounded gate nMOSts is modelled accounting for the specific conditions applied by CDM ESD stress. The impact of the gate length on the CDM-specific bipolar saturation mode is addressed. The different operation modes occurring during CDM ESD stress translate to self-heating which explains the observed test results.     

Matrix isolation vibrational spectra of alkyl chalcogenides complexed with HCl: Structure of alkyl sulfide and alkyl selenide complexes with hydrochloric acid in ar matrices from infrared spectra

The matrix isolation technique has been used to isolate the hydrogen-bonded complexes of hydrochloric acid with some methyl and ethyl sulfides and selenides. In the ir spectra the perturbed vibrational mode of the complexed acid was observed as a rather complicated, broad band which exhibits multiplet structure. Evidence was obtained for the coexistence of 1:1, 2:1 and 1:2 complexes. The shifts Δν_ClH… of the 1:1 complexes correlate with the proton affinity values of the chalcogenide bases. Isotopic dilution experiments using DCl allowed us to determine a bifide structure for the 1:2 R₂X · (HCl)₂ complexes.     

Conformational isomerism of ethyl chalcogenides in inert matrices: Influence on the νs band structure of H-bonded complexes with HCl

Evidence is presented to indicate that the compounds (C₂H₅)₂S and (C₂H₅)₂Se exhibit conformational isomerism in low-temperature Ar and N₂ matrices. This phenomenon contributes to the width and structure of the infrared ν_s vibration band of HCl in complexes with these chalcogenides.     

NBTI reliability of Ni FUSI/HfSiON gates: Effect of silicide phase

In this work, we investigate the negative bias temperature instability (NBTI), when Ni-rich (Ni₂Si and Ni₃₁Si₁₂) silicides are used as gate electrodes on HfSiON and compare them to Ni mono-silicide (NiSi). The study also investigates the influence of increased pre-metal deposition (PMD) temperature and decreased silicide thickness on NBTI.Our study demonstrates that, when initial threshold voltage differences are taken into account and comparisons are performed at the same oxide electric field, no significant differences in intrinsic NBTI behavior are found for devices with different Ni silicide gate electrodes. In addition, we performed an Arrhenius study showing similar activation energies, indicating that no favorable conditions for dielectric degradation are created by the increased amount of Ni.     

Effects of Al2O3 Dielectric Cap and Nitridation on Device Performance, Scalability, and Reliability for Advanced High- κ/Metal Gate pMOSFET Applications

A pFET threshold-voltage (Vt) reduction of about 200 mV is demonstrated by inserting a thin Al₂O₃ layer between the high-k dielectric and the TiN gate without noticeable degradation of other electrical properties. HfSiO_propcapped with 9 Aring of thin Al₂O₃obtains a low long-channel Vt of -0.37 V (the lowest among those with TiN gate), a high mobility of 59 cm² /V ldr s at 0.8 MV/cm (92% of universal value), a negligible equivalent- oxide-thickness (EOT) increase of 0.1 Aring (compared to the uncapped reference), and a low Vt instability of 4.8 mV at 7 MV/cm. It also passes the ten-year negative-bias-temperature-instability (NBTI) lifetime specification with a gate overdrive of -0.7 V. This indicates that thin Al₂O₃obtains caps are beneficial to the pFET applications. In contrast, nitrogen incorporation in the Al₂O₃-capped HfSiO_prop is not favorable because it increases the Vt by 50-140 mV, degrades the mobility by 10%-22%, increases the EOT by 0.5-0.8 Aring and the Vt instability by 5-13 mV, and reduces the NBTI lifetime by four to five orders of magnitude. Compared to postcap nitridation, high-k nitridation results in more severe degradation of these properties by incorporating nitrogen closer to the Si/SiO₂ interface.     

Silica-supported chromium oxide: colloids as building blocks

In this contribution, the formation and immobilisation of chromium(iii) hydroxyoxide colloids is investigated. Nano-sized Cr(iii) colloids are generated in situ upon reduction of Cr(vi), dosed to a stirred reactor. The growth of the elementary colloids by the consumption of solved Cr is kinetically unfavorable compared to their aggregation to larger secondary particles, the size of which depends on the concentration of the building block colloids. This aggregation process can be steered by simple process parameters such as dosing rate and concentration of the Cr(vi). The Cr(iii) colloids are immobilised in situ on a support material via precipitation chromatography. Upon drying, the initially amorphose hydroxyoxides are gradually transformed into crystalline Cr(2)O(3) nanoparticles, mainly located at the external surface of the support. This approach opens new opportunities for the synthesis of supported metal oxide catalysts.     

A Printable Photopolymerizable Thermosensitive p(HPMAm‐lactate)‐PEG Hydrogel for Tissue Engineering

Bioprinting is a new technology in regenerative medicine that allows the engineering of tissues by specific placement of cells in biomaterials. Importantly, the porosity and the relatively small dimensions of the fibers allow rapid diffusion of nutrients and metabolites. This technology requires the availability of hydrogels that ensure viability of encapsulated cells and have adequate mechanical properties for the preparation of structurally stable and well‐defined three‐dimensional constructs. The aim of this study is to evaluate the suitability of a biodegradable, photopolymerizable and thermosensitive A–B–A triblock copolymer hydrogel as a synthetic extracellular matrix for engineering tissues by means of three dimensional fiber deposition. The polymer is composed of poly(N‐(2‐hydroxypropyl)methacrylamide lactate) A‐blocks, partly derivatized with methacrylate groups, and hydrophilic poly(ethylene glycol) B‐blocks of a molecular weight of 10 kDa. Gels are obtained by thermal gelation and stabilized with additional chemical cross‐links by photopolymerization of the methacrylate groups coupled to the polymer. A power law dependence of the storage plateau modulus of the studied hydrogels on polymer concentration is observed for both thermally and chemically cross‐linked hydrogels. The hydrogels demonstrated mechanical characteristics similar to natural semi‐flexible polymers, including collagen. Moreover, the hydrogel shows suitable mechanical properties for bioprinting, allowing subsequent layer‐by‐layer deposition of gel fibers to form stable constructs up to at least 0.6 cm (height) with different patterns and strand spacing. The resulting constructs have reproducible vertical porosity and the ability to maintain separate localization of encapsulated fluorescent microspheres. Moreover, the constructs show an elastic modulus of 119 kPa (25 wt% polymer content) and a degradation time of approximately 190 days. Furthermore, high viability is observed for encapsulated chondrocytes after 1 and 3 days of culture. In summary, we conclude that the evaluated hydrogel is an interesting candidate for bioprinting applications.     

Generative probabilistic models extend the scope of inferential structure determination

Conventional methods for protein structure determination from NMR data rely on the ad hoc combination of physical forcefields and experimental data, along with heuristic determination of free parameters such as weight of experimental data relative to a physical forcefield. Recently, a theoretically rigorous approach was developed which treats structure determination as a problem of Bayesian inference. In this case, the forcefields are brought in as a prior distribution in the form of a Boltzmann factor. Due to high computational cost, the approach has been only sparsely applied in practice. Here, we demonstrate that the use of generative probabilistic models instead of physical forcefields in the Bayesian formalism is not only conceptually attractive, but also improves precision and efficiency. Our results open new vistas for the use of sophisticated probabilistic models of biomolecular structure in structure determination from experimental data.