Offers : 15
Investigation of the ageing mechanisms in Silicon-based Lithium-ion batteries by coupling in situ and operando scattering techniques with electrochemical characterizations
Start date : 1 April 2017
offer n° PsD-DRF-17-0006
An 18-month post-doctoral position is offered at the Institute for Nanoscience and Cryogenics (INAC) at Grenoble, France. INAC is a joint CEA-UGA research institute. It is a major actor in fundamental research on condensed matter, soft matter and cryogenics. Research programs on energy conversion and storage are focused on the characterization of the structure and properties of nanomaterials using cutting-edge techniques, including Large Scale Facilities.
The post-doctoral position is offered in the framework of a European H2020 project dedicated to develop Silicon-based Lithium-ion batteries with improved operation time. Our task is to provide understanding of ageing mechanisms in composite electrodes by means of cutting-edge in situ and operando scattering techniques on lab instruments and at world-class Large Scale Facilities (synchrotron radiation and neutrons), coupled with electrochemical characterizations.
- Keywords : Engineering science, Materials and applications, Physical chemistry and electrochemistry, INAC, SyMMES
- Laboratory : INAC / SyMMES
- CEA code : PsD-DRF-17-0006
- Contact : firstname.lastname@example.org
Cleaning of graphene by pulsed plasma etching: optimization and multi-scale characterization by advanced photoemission techniques
Start date : 1 May 2017
offer n° PsD-DRT-17-0037
The objective of this one-year post-doc is to address both issues by systematic, multi-scale surface analysis of transferred graphene surfaces treated by pulsed plasmas developped in the Clean-GRAPH ANR project (2013-2016). We will be employing advanced photoemission techniques to provide direct insights on chemical electronic states, work function and band structure.
Samples will be characterized using on the hand macro-scale, area-averaged high-resolution X-ray Photoelectron Spectroscopy (XPS) for chemical state fingerprinting and quantification; on the other hand, complementary microscopic analysis will be performed using PhotoElectron Emission Microscopy (PEEM) techniques, either in direct space to retrieve local work function information, or in reciprocal space (kPEEM) for imaging of the electronic band structure. kPEEM in particular will provide direct insights on the effectiveness of plasma cleaning and impact on electronic properties by qualitative and quantitative changes in the ?-band dispersion in k-space at the micron scale.
- Keywords : Engineering science, Materials and applications, Solid state physics, surfaces and interfaces, DTSI, Leti
- Laboratory : DTSI / Leti
- CEA code : PsD-DRT-17-0037
- Contact : email@example.com
Wireless biological sensor using 2D materials (Graphene , Molybdenium disulfide)
Start date : 1 November 2016
offer n° PsD-DRT-16-0115
The main goal of the post-doctoral position is the fabrication of a biological sensor using 2D materials and that can be remotely addressed thanks to a RF antenna simultaneously fabricated alongside the biosensor.
The post-doctoral associate will be in charge of the fabrication and characterization of the prototype. Starting from well-designed modelling, he/she will first establish a design architecture for the sensor and RF antenna. Once designed and sized, the post-doctoral associate will adapt existing transfer protocol of 2D materials to develop an innovative fabrication process for the sensor. He/she will then fabricate the first prototypes of the sensors. Consecutively he/she will validate first the remote addressing of the sensor via the RF antenna. Secondly he/she will lead biodétection tests to assess the sensitivity of the fabricated sensors. Finally, he/she will try to integrate Transition Metal Di-chalcogenides 2D materials (such as MoS2) to graphene sensors inside a hybrid 2D materials biological sensor. The goal here will be to boost operational sensitivity.
- Keywords : Engineering science, Instrumentation, Solid state physics, surfaces and interfaces, DCOS, Leti
- Laboratory : DCOS / Leti
- CEA code : PsD-DRT-16-0115
- Contact : firstname.lastname@example.org
Frequency tunable elastic plate wave resonators and filters
Start date : 1 March 2017
offer n° PsD-DRT-17-0011
The increasing number of frequency bands having to be dealt with in mobile phone systems require a huge number of band pass filters in such systems. In this context, the capability to provide frequency tunable resonators and filters is seen as a key enabling element in future wireless transmission systems.
CEA-LETI has been working for more than 10 years on the development of resonators and filters exploiting the propagation of guided elastic waves in piezoelectric thin films. It has also proposed several concepts for frequency agile resonators and filters.
The purpose of this post-doc will be to further develop these ideas and to apply them to the design of demonstrators matching realistic specifications. In collaboration with the other member of the project team, more focused on fabrication in clean rooms, the candidate will propose innovative structures demonstrating frequency tuning of reconfigurability, and will take in charge their electrical characterization.
- Keywords : Engineering science, Electronics and microelectronics - Optoelectronics, Mathematics - Numerical analysis - Simulation, DCOS, Leti
- Laboratory : DCOS / Leti
- CEA code : PsD-DRT-17-0011
- Contact : email@example.com
Optimisation of the monolithic cascode device based on GaN/Si MOS-Channel HEMT technology
Start date : 1 February 2017
offer n° PsD-DRT-17-0017
In order to adress the requirements of power conversion in the field of electrical vehicule or photovoltaics, high performance GaN on Silicon power devices need to be developped. Such power devices must fulfill agressive specifications in terms of threshold voltage (> 2V), nominal current (100-200A), breakdown voltage (650 and 1200V) and stability (low “current collapse”, low hysteresis). Discrete cascode configuration, consisting in a combination of a low voltage E-mode Silicon die and a hihg voltage D-mode GaN/Si die in a single package, has been developped by different laboratories and companies to adress this need (Transphorm, On-Semi, NXP, IR…). However, this approach has some drawbacks like parasitic inductances, device pairing, need of additionnal protection devices, cost, temperature limitation due to the Si die…
The monolithic cascode is a very compact version of the cascode configuration that will allow to avoid those problems but also to improve the performance of E-mode devices developped at Leti (MOS-channel HEMT). Indeed, some actors in the field of GaN power devices already use this configuration with another E-mode technology (p-GaN gate).
Monolithic cascode device has been demonstrated recently by CEA-Leti in the frame of a PhD thesis (2014-2016) on the basis of the 200mm GaN/Si, CMOS compatible, MOS-channel HEMT technology. The aim of this post-doc is to optimize the monolithic cascode structure in terms of On-state resistance, Figure Of Merit, switching losses and high switching frequency capability in order to meet the specifications of our industrial partners.
- Keywords : Engineering science, Electronics and microelectronics - Optoelectronics, DCOS, Leti
- Laboratory : DCOS / Leti
- CEA code : PsD-DRT-17-0017
- Contact : firstname.lastname@example.org