Electro-optical characterisation for Vis-IR active devices
With the Integration of Heterogeneous Components Department, the Lab of Technologies and Components for Visualisation (DIHS/LTCV) develops OLED devices. One of its main topics is aimed at producing hybrid OLEDs, hybrid standing for the mix of deposition techniques : wet and evaporation. Target applications come from micro displays to photodetectors via lighting.
For the development of hybrid OLEDs, DIHS/LTCV lab is looking for a Post_doc specialised in Organic Electronic to work in a fundamental research project. You will be in charge of stack development and of the characterisation method development for OLEDs devices.The optimisation of the cavity will be done based on the physical parameters of the different layers.
At the same time, IV, CV and photoluminescence analyses will be adapted in visible and IR range.
Finally, the layers interface study by impedance spectroscopy and Hall effect will be done.
New nanostructurated fluorescent materials for the detection of volatile organic compounds.
The presence in indoor environments of many substances and (geno-)toxic, allergenic and infectious agents with pathogenic effects is well known. The on-site detection of these
substances has become a strong need, related to public health concerns. To respond to this need and enable the development of sensitive and selective ’field-deployable chemical sensors’, different technological solutions are being considered (conductimetric, electrochemical, piezoelectric, electro-mechanical, optical based systems…). Among all these methods, those based on the use of fluorescence phenomena are particularly interesting because of the inherently high sensitivity (lower limit of detection) of the technique and the possibility it offers to develop low cost, small size and low
energy consuming devices.
The proposal falls into this context and aims at evaluating the potentialities of new nanostructurated organic materials for the detection of indoor air trace pollutants by fluorescence change monitoring. This work will be done in straight collaboration with the Laboratoire Chimie des Polymères (UMR7610-CNRS/UPMC Paris VI) specialized in the synthesis
of functionalized organogels. More precisely, we propose to develop new highly porous supramolecular materials serving either as substrate for the sensitive fluorescent polymer or functionalised so as to directly detect and recognize the vapor pollutant.
The physico-chemical properties of these new materials will be examined by different techniques. Their performances in the presence of target pollutants (formaldehyde, acetaldehyde) and potentially interferants will be evaluated. Finally, the most interesting materials will be integrated into a functional prototype.
Developement of a simulation platform for the energy systems
The evolution of power systems towards smart-grids, including a high share of renewable generation which can be combined with storage systems, lead to an increased complexity for designing and optimizing these systems. This leads to a need for new modeling and simulation tools, which have to manage different energy sources, different energy vectors and different technologies for energy conversion. Moreover, such simulation tools will be used to optimize the system sizing and to design energy management strategies.
The objective of this project is to design the software architecture for the simulation platform, which will be in ad equation to the previously mentioned needs. Such software will be organized in order to maximize the transfer towards industrial partners. The software will be able to support multi-energy systems, and will leave the possibility for the user to implement its own component models or energy management strategies.
The project is focused on the simulation platform architecture, and on the architecture model. This architecture will be used as a base for the development of a software. The objective of the given project is not to cover all the applications but rather to validate the architecture through a given application.
Development and characterization of concentrator photovoltaic (CPV) receivers for high-efficiency CPV modules
Concentrator photovoltaics (CPV) arises as a promising technology capable of economically justify the use of highly efficient (and highly expensive) monolithically stacked multijunction solar cells (MJSC). CPV takes advantage of low-cost optical elements, such as mirrors or lenses, to capture the sunlight and concentrate it into small-size cells, exchanging solar cell surface by optical elements. This technology, which is at an industrial stage, uses state-of-the-art triple junction (3J) solar cells with efficiencies up to 45%.
The postdoc position here proposed will deal with novel architectures of CPV receivers conceived from high-efficiency MJSC that will be integrated in next-generation CPV modules. The research engineer will also need to learn how to characterize these systems, for which he/she will use the tools available at the CPV Lab at INES (CEA). Novel characterization techniques may also be required.
The candidate must have a M.S. in Physics or Engineer with specialization on solid state physics, electronics, electrical engineering, mechatronics or similar. He/she must be a PhD, preferably in the field of photovoltaics and particularly on CPV. Good language skills and laboratory experience are required.
Development of new processes for the fabrication of advanced interconnect structures of solar cells
The fabrication of solar cells with high performances at a reduced cost is a key challenge addressed by many research institutions and industrials worldwide. Many technological solutions are being investigated. Among them, a promising approach consists in forming narrower metal lines to limit shadowing of active areas of the cells. This work aims at replacing serigraphy by new fabrication processes able to reduce line width. For this purpose, the conducting substrate is coated by an insulating mask in which the lines are defined. The metal is then directly plated selectively onto the weakly conducting portions of the substrate, i.e. the lines, using electrolytic reactions. The process conditions will be adapted with regard to the nature of the initial conducting surfaces.
Production of green hydrogen and ammonia from offshore energy
This subject is dedicated to the high potential of offshore wind power in the high seas, where it seems extremely complicated and expensive to install an electric transmission to a continental grid. In addition, the IMO, a United Nation agency that is responsible for environmental impacts of ships, adopted ambitious targets to reduce greenhouse gas (GHG) emissions from marine shipping. The IMO plan regulates carbon dioxide (CO2 ) emissions from ships and requires shipping companies to halve their GHG emissions by 2050 (compared to 2008 levels).
Different ways are being explored in order to identify the best low-carbon fuel that will be able to power new marine propulsion systems without GHC emissions (and others polluants like Sox, Nox…).
Hydrogen combined with a fuel cell is a good option for small application (fishing boat…). However, issues associated with hydrogen storage and distribution (low energy density) are currently a barrier for its implementation for large and massive marine application which drivess 80–90% global trade, moving over 10 billion tonnes of containers, solid and liquid bulk cargo across the world’s oceans annually.
Hence, other indirect storage media are currently being considered. Of these, ammonia is a carbon free carrier which offers high energy density. First studies and demonstration projects show that it could be used as a fuel coupled with a new generation of high-temperature fuel cells (SOFC) or internal combustion engines.
This project focuses on the green ammonia production on a high seas platform including an offshore wind farm that use renewable electricity to first generate hydrogen from water (via electrolysis) and nitrogen from air and then combine both in a Haber-Bosch process to synthesize ammonia. The objective is to develop modeling tools (Modelica / Dymola environment) in order to build, simulate and optimize "wind to ammonia" systems and energy management solutions to minimize the production cost of ammonia.
Kinetic study of biocide effect in nanocellulose_based food film
This project will study the kinetic of biocide effect of a nanocellulose-based film food. The main aim is to graft Ag and/or ZnO NPs on and inside halloysite particles that have a characteristic shape of twisted sheets and therefore could acting as NPs tanks. The localization of NPs outside halloysite could induce a fast biocide effect with limited duration whereas the internal grafting could produce longer biocide effect. This project gathers all steps from the film food synthesis, its nanocharacterization to the evaluation of its toxicological effect on bacteria. The final goal is to find one or many halloysite functionalizations allowing to extend the biocide effect in film food and to transpose it to other types of materials.
Silicon nanowire elaboration for microelectronic applications
In order to realize high capacity integrated capacitor, one approach consists in developing electrode with high specific surface. In this work, we propose to perform capacitor integrating silicon nanowires. The first part of this study will be devoted to the understanding and to the optimization of Si nanowires CVD growth process. In parallel, properties of nanowires obtained by electrochemical silicon etching will be assessed and will be compared to CVD nanowires characteristics. According to the electrical performances, different strategies (metallization Silicuration…) will be envisaged in order to enhance their electrical conductivity.
New Sustainable Carbon Catalysts for PEMFC
The aim of the project is to develop and test for ORR, a mesoporous and graphitised graphene aerogel based material, presenting a hierarchical structuring allowing a better material transfer and graphitic domains increasing the durability and conductivity of the final material, and functionalised by Pt-NPs.
These graphene-based structures developed at IRIG/SyMMES possess surface chemistries and micro/meso/macro porosities that depend on the synthesis, functionalisation and drying methods used. The aim will be to increase their degree of graphitisation, and then to deposit Pt-NPs by chemical means. The electrocatalytic properties of these materials will then be tested.
Advanced meso-structural characterisation of these materials by scattering (X-ray or neutrons) methods will enable to investigate the structural properties of these new electro-catalysts. These properties will thenbe correlated to their electrocatalytic properties, and performances in fuel cell systems. This knowledge will be gained through ex-situ and operando analyses.
Low temperature process modules for 3d coolcube integration : through the end of roadmap
3D sequential integration is envisaged as a possible solution until the end of CMOS roadmap. Different process modules have been developped @ 500°C for planar FDSOI technology in a gate first process. However, regarding bottom transistor level stability in CoolcubeTM integration, and yield consideration, the need to reduce further the top transistor temperature down to 450°C should be explored.
The post-doc will have in charge the development of specific technological modules at low temperature both 500°C and 450°C for FDSOI planar devices to acquire a solid knowledge in low temperature CMOS process integration. The specific low temperature gate module will be addressed on planar devices. The threshold voltage modulation will also be studied.
The work will be performed in collaboration with the technological platform process of LETI for the low temperature modules development. The electrical characterization in collaboration with the characterization laboratory and the TCAD simulations team of LETI.