They are studying the adhesion of thin SiCN films (40 to 120nm thick) deposited on Cu (a few µm) itself deposited on a 300mm Si substrate (550µm thick). They especially focus on the impact of the SiCN deposition process (and surface preparation) on the final adhesion energy.

They use an original approach based on the Colored Picosecond Acoustic Technique to evaluate adhesion in a quantitative manner. Such a technique uses ultra high frequency acoustic waves to probe the interface quality. they would like to compare our results to those obtained using a well-recognized technique like 4 points bend adhesion testing.

They are looking for a research group to collaborate with on that subject. An expertise on 4 points bend technique and especially applied to microelectronic samples and ultra-thin films is preferred.

Preliminary 4 points bending measurements on similar samples revealed an adhesion energy in the range 2 to 20 J/m² . Those results have been obtained using a force not higher than 50 N and the displacement was in the range 60-80 µm before delamination.

For more information, or collaboration please contact Dr. Arnaud Devos, at IEMM, Lille in France (arnaud.devos@isen.fr)

IMDEA Materials (Madrid Institute for Advanced Studies of Materials) is seeking for an innovative and skilled microscopist able to contribute to the application of advanced microscopy techniques (FIB, SEM, EBSD, EDS, TEM) to the characterization of materials, including the use of these techniques to carry out in-situ mechanical tests at the micro and nanoscale.

The selected candidate will assist other researchers (including external users) in the use of the microscopy facilities, will manage the electron microsocopy lab,  and will be encouraged to develop his own research lines in the area of electron microscopy.

 Requirements:

Candidates should have a PhD in Materials Engineering or Physics.

The applicant must be an experienced transmission electron microscopist, with accredited experience in:

• High-resolution electron microscopy (HREM).
• Electron diffraction and CBED analysis.
• BF/DF imaging, including weak-beam conditions for dislocation/interface analysis.
• STEM HAADF and chemical mapping.
• TEM tomography.

A good background in the use of SEM, EBSD and FIB, as well as in nanomechanical testing, will be strongly valued.

Fluent English is required.

More information and application at the following link: http://jobs.materials.imdea.org/offer/104

Context:

Power electronics applications have expanded in many fields such as domotics or energy conversion, but their reliability is mostly critical in the transportation field and off-shore applications. Anticipating or even preventing their failure is a key technical issue.

In recent years, several weak spots have been identified in the structure of modern Silicon-based power MOSFETs and IGBTs, and some solutions have been found to increase their resistance to disruption (solder, packaging...). However, the aging of the top metal source, mainly made of Aluminum or Aluminum alloy has persisted as an intrinsic phenomenon, which degrades the electrical performance of the device over time. The deterioration of the Al layer occurs through mechanisms that involve grain boundary diffusion, crack formation and surface oxidation, also driven by stresses arising from thermal mismatch between the metal and the silicon. Similar oxidizing cracks develop between the metallization and the wire bondings, leading to local failure of the device [2].

References:

1. D. Martineau, C. Levade, M. Legros, P. Dupuy, and T. Mazeaud. “Universal mechanisms of Al metallization ageing in power MOSFET devices.” In: Microelectronics Reliability 54.11 (2014), pp. 2432–2439.

2. R. Ruffilli et al., Mechanisms of power module source metal degradation during electro- thermal aging. Microelectronics Reliability (2017).

Objectives:

The study will focus on the aluminum layer of the power device that interfaces the silicon die and the electrical circuit.

The objective of this thesis is to find technical ways to slow down the mechanisms that cause the deterioration of the Aluminum layer, either by increasing the metallic contact between the wire bondings and the metal in the initial state and/or to restore this electrical contact during operation.

From September 2019

Mainly at the CEMES in Toulouse (85% time).

Regular visits are planned to Mitsubishi Electric R&D Centre Europe, Rennes.     

Education and experience required:

 • Engineer's degree or Master's degree with a focus in Materials Science

• Simulation and programming softwares (COMSOL Multiphysics, Python)

• Competence in materials characterization tools (TEM, FIB)

• Strong general scientific knowledge and multidisciplinary opening (materials science, electrical, mechanical, thermal, chemical, mathematical)

• Power electronics skills would be a plus

• Communication and writing skills in English

• Motivation and dynamism to work in a research environment

• Ability to work in a multicultural and international environment

Send your CV and motivation letter in a pdf format by mail (by specifying in object: your name and the reference JCB_PhD_2019CEMES):

jobs@fr.merce.mee.com, marc.legros@cemes.fr

The Laboratoire d’Étude des Microstructures et de Mécanique des Matériaux, LEM3 and The Max-Planck-Institut für Eisenforschung GmbH, MPIE are looking for a Postdoctoral Researcher on:

"Influence of the microstructure on the internal stress field within grains."

Your tasks:

- You will perform detailed analyses of deformation microstructures. You will explore cutting-edge techniques for characterizing defects.

- You will perform numerical simulations of microstructures evolution.

- You will share your time between Metz (France) and Düsseldorf (Germany).

- Your results will be discussed in the framework of fundamental deformation mechanisms of materials. 

Your profile:

- You should be a PhD in materials science. (PhD defense must be in 2016, 2017, 2018 or 2019)

- You should have good knowledge of deformation physics and plasticity of materials.

- Experience with electron microscopes is expected.

- Experience with numerical simulations will be a plus.

More information on subject and application are available in the following document: « Postdoc_LEM3_MPIE.pdf »

Or please contact:

Dr. Vincent TAUPIN : vincent.taupin@univ-lorraine.fr

Dr. Antoine GUITTON : antoine.guitton@univ-lorraine.fr

The Ceramics group at the Department of Materials and Earth Science at TU Darmstadt focusses on the development of new functional ceramics is looking for a Postdoctoral Researcher on TEM.

Your tasks:

Research work will be mostly of experimental nature with accompanying data analysis. Your major task will be preparing TEM samples, performing TEM analyses (free access to TEM facilities in-house), and provide insights on the microstructures (dislocation structures, grain boundaries) in the areas of interest in ceramic oxides.

Your profile:

Excellent Ph.D. in materials science, chemistry or physics, first-hand experience in TEM characterization, and several internationally refereed publications. Very good knowledge of English in writing and speaking.

A background in one or more of the following topics is required: TEM investigations into atomic structure, dislocations, plastic deformation.

Your application:

Applications should include CV, publication list, and PDFs of 3 recent publications. Please send your application to: apply@ceramics.tu-darmstadt.de

Application deadline: June 10, 2019

More information can be found in the following document: « TEM_PostDoc_TUDarmstadt.pdf »