Thesis defense of Damien NOUGUIER, for a doctoral thesis of the University of Grenoble Alpes , speciality "NANO ELECTRONIC & NANO TECHNOLOGIES ", entitled:
Amphi M001 - Phelma/Minatec 3 rue parvis Louis Néel 38016 Grenoble cedex1
« Statistical study and modeling of NBTI degradation for FDSOI and BULK in CMOS technologies. »
Friday, September 28th, 2018 at 10:00
The microelectronics industry is able to design transistors reaching dimensions of the order of ten nanometers. And doing this, we reaching the limits in terms of size reduction of CMOS transistors. At these dimensions, the reliability and variability of the devices is critical in terms of lifetime prediction and component warranty. Among the critical aspects, NBTI (Negative Bias Temperature Instability) degradation represents one of the biggest challenges in terms of reliability. This degradation coming from a charge trapping in the gate oxide is responsible for a large part of the degradation of the transistors. Performing a huge experimental work based on the characterization of the kinetic of degradation and relaxation of the NBTI degradation with rapid measurements, allowing us to work on the modeling of the stress and relaxation phases of NBTI degradation. We have successfully create a model for stress and relaxation of the NBTI degradation. These models were then tested on several technological nodes from 14nm FDSOI to 180nm Bulk. We also study the impact of some process changes on NBTI degradation. Finally, we propose a detailed study of the variability induced by the NBTI and the DCM model (Defect centric Model) allowing to model this variability. We also propose a mathematical correction of this model but also another mathematical expression of this model allowing to use it for a large number of defects. Enfin, nous prouvons que DCM est défectueux dans sa prédiction du nombre de défauts et nous proposons un nouveau modèle sous la forme d'un DCM avec deux défauts ou DDCM (Dual Defect Centric Model).