General information
Organisation
The French Alternative Energies and Atomic Energy Commission (CEA) is a key player in research, development and innovation in four main areas :
• defence and security,
• nuclear energy (fission and fusion),
• technological research for industry,
• fundamental research in the physical sciences and life sciences.
Drawing on its widely acknowledged expertise, and thanks to its 16000 technicians, engineers, researchers and staff, the CEA actively participates in collaborative projects with a large number of academic and industrial partners.
The CEA is established in ten centers spread throughout France
Reference
SL-DRT-26-0594
Direction
DRT
Thesis topic details
Category
Technological challenges
Thesis topics
Reliability and dynamic properties of GaN high electron mobility transistors : backbarrier and substrate type impact
Contract
Thèse
Job description
The rapid expansion of AI and cloud computing has placed unprecedented demands on data center infrastructure, where energy efficiency is now a defining constraint. Despite their potential, many power systems still rely on silicon-based devices, which suffer from inherent efficiency limitations that result in significant energy losses. GaN HEMTs, with their superior electron mobility and high breakdown voltage, represent a compelling alternative, capable of achieving far higher efficiencies in power conversion. However, their broader adoption is constrained by reliability challenges, particularly those arising from charge trapping mechanisms that degrade device performance over time.
In this PhD project, you will delve into the fundamental dynamics of charge carriers in GaN HEMTs, focusing on the physical origins of on-resistance and threshold voltage drifts—key indicators of device instability. By systematically analyzing the electrical behavior of these transistors under various operating conditions, you will uncover the mechanisms behind their degradation and identify pathways to enhance their robustness. Your findings will directly inform the optimization of device architectures, enabling the development of more efficient and reliable power electronics that can meet the demands of modern data centers and beyond.
You will be part of a multidisciplinary research team at CEA-Leti, collaborating with experts in semiconductor material engineering, device simulation, and electrical characterization. This environment will provide you with a comprehensive skill set, spanning process engineering, advanced electrical testing, and TCAD simulations, This position will not only expand your expertise but also position you at the forefront of a field with global impact. By contributing to the advancement of GaN HEMTs, you will play a key role in shaping the future of power electronics—where innovation directly translates into sustainable technological solutions.
University / doctoral school
Science de l'Ingénierie et des Systèmes (ENGSYS)
Lille I
Thesis topic location
Site
Grenoble
Requester
Position start date
01/10/2026
Person to be contacted by the applicant
LAVIEVILLE Romain
romain.lavieville@cea.fr
CEA
DRT/DCOS//LCEF
Laboratoire de caractérisation et de fiabilité(LETI / DCOS / SCCS / LCEF)
CEA Grenoble, bat 51B
17 avenue de Martyrs
38054 Grenoble
04 38 78 37 89
Tutor / Responsible thesis director
MEDJDOUB Farid
IEMN
UMR CNRS 8520
Cité Scientifique
Avenue Poincaré BP 60069
59652 Villeneuve d'Ascq Cedex - France
En savoir plus
https://www.linkedin.com/in/rlavieville/
https://www.leti-cea.fr/cea-tech/leti
https://www.youtube.com/watch?v=UJqY00xPWmY&list=PL3_a7egKrpI49r2F-euhMe03x0iBjJs-d&index=3