Ageing of laser crystallized and unhydrogenated polysilicon thin film transistors

Ageing of low temperature polysilicon Thin Film Transistors (TFTs) is reported in this study. The active layer of these high performances transistors is amorphous deposited using Low Pressure Chemical Vapor Deposition (LPCVD) technique and then laser crystallized using a single shot ECL (SSECL of SOPRA) with very large excimer laser. The drain and source regions are in-situ doped during the LPCVD deposition by using phosphine or diborane to fabricate n-type or p-type transistors respectively.These laser crystallized TFT's show poorer reliability properties than solid-phase crystallized TFT's. This poor stability is explained to originate from the high surface roughness produced by the laser crystallization, which is highlighted from Atomic Force Microscopy observations.Moreover to this conclusion, the behaviour of the threshold voltage shift ΔV_T during positive and negative stresses is checked to the light of a stretched exponential law that is, as supposed, a federative law. This law is explained in hydrogenated amorphous silicon TFT's by a dispersive diffusion coefficient of hydrogen in the disordered material. Taking into account that such relation appears as sufficiently general and, particularly, can describe the behaviour of monocrystalline silicon MOSFET and un-hydrogenated polysilicon TFT's where the hydrogen cannot involved, it can be supposed that it deals with disordered materials and disordered regions in crystalline materials (interface, grain boundary, …..).     

Influence of some factors affecting antibacterial activity of PVA/Chitosan based hydrogels synthesized by gamma irradiation

Poly (vinyl alcohol) hydrogels containing different concentrations of chitosan with molecular weight of 471 and 101 kDa were crosslinked by gamma irradiation at a dose of 25 kGy. The swelling behavior, gel content and morphological structure of the blend were investigated. The antibacterial effect, as a function of chitosan content and molecular weight in the hydrogel, was investigated against Escherichia coli and Bacillus subtilis. With increasing chitosan content the equilibrium degree of swelling of the blend increased and the gel fraction decreased. Results of antibacterial activity of chitosan revealed that chitosan was more effective in inhibiting growth of gram positive bacteria than that of gram negative ones. It was observed that, the chitosan content as well as its molecular weight has a direct influence on bacteria growth inhibition. The higher the chitosan content in the blend and the higher its initial molecular weight, the larger was the inhibition zone diameter. The bacteria growth inhibition was attributed to the diffusion of entrapped chitosan from the hydrogel blend to the culture medium.     

Corrosion Behavior of Shiny Side and Dull Side of Aluminum Foil in 0.3% Wt NaCl Non Agitated Solution: Appearance of Rhombus form Corrosion Morphology

Protection of Metals and Physical Chemistry of Surfaces - We have investigated the corrosion behavior of shiny and dull faces of aluminum household foil in 0.3 wt % NaCl nonagitated solution. The...     

Low sensitivity to temperature compressive-strained structure quantum well laser Ga1−xInxAs1−yNy/GaAs

The objective is to exploit the properties of the GaInNAs/GaAs alloy compressive strain structure to design a laser diode likely to meet the needs of optical communications. Modelling concerns mainly the study of the potentialities of thermal stability and dynamic response offered by these new techniques of electric and optical confinement. Band structure is modelled and typical quantum well properties are illustrated. A thorough study of the structural parameters is undertaken to take into account from the design criteria the temperature sensitivity. Minimising the Auger coefficient in the order of 10⁻²⁹ cm⁶/s appears to allow achieving efficient laser diodes production.     

Relation Between Mechanical Instabilities and Corrosion Sensitivity of Aluminum Body Cans Surfaces

Protection of Metals and Physical Chemistry of Surfaces - In this work we investigated the mechanical and corrosion behavior of aluminum can bodies. The results obtained show homogeneous...     

Big Data to support sustainable urban energy planning: The EvoEnergy project

Energy sustainability is a complex problem that needs to be tackled holistically by equally addressing other aspects such as socio-economic to meet the strict CO₂ emission targets. This paper builds upon our previous work on the effect of household transition on residential energy consumption where we developed a 3D urban energy prediction system (EvoEnergy) using the old UK panel data survey, namely, the British household panel data survey (BHPS). In particular, the aim of the present study is to examine the validity and reliability of EvoEnergy under the new UK household longitudinal study (UKHLS) launched in 2009. To achieve this aim, the household transition and energy prediction modules of EvoEnergy have been tested under both data sets using various statistical techniques such as Chow test. The analysis of the results advised that EvoEnergy remains a reliable prediction system and had a good prediction accuracy (MAPE  5%) when compared to actual energy performance certificate data. From this premise, we recommend researchers, who are working on data-driven energy consumption forecasting, to consider merging the BHPS and UKHLS data sets. This will, in turn, enable them to capture the bigger picture of different energy phenomena such as fuel poverty; consequently, anticipate problems with policy prior to their occurrence. Finally, the paper concludes by discussing two scenarios of EvoEnergy development in relation to energy policy and decision-making.     

Illustrative Discussion of MC-Dropout in General Dataset: Uncertainty Estimation in Bitcoin

Neural Processing Letters - The past few years have witnessed the resurgence of uncertainty estimation generally in neural networks. Providing uncertainty quantification besides the predictive...