Skip to Main content Skip to Navigation

Développement de procédés de gravure plasma sans dommage pour l'électronique de puissance à base de GaN

Abstract : In power electronics, GaN has become a material of choice: it meets the challenges of high energy performance, while promoting compactness and lightness of the components. When manufacturing power devices based on an AlGaN / GaN heterostructure, plasma etching induces degradations in the material and reduces the electronic properties of the components, in particular diodes and HEMT (High Electron Mobility Transistors). These thesis works focused on the study of these degradations and proposes industrializable etching processes which reduce these plasma impacts. We first focused on the degradation mechanisms involved during the etching of SiN with stop on AlGaN, according to different plasma parameters. The electrical and physicochemical characterizations (in particular the XPS) made it possible to highlight various degradation mechanisms and to propose a synthetic model. We have identified two main factors of electrical degradation: the first one is the energy ion bombardment which modifies the surface stoichiometries, favors the implantation of contaminants, disturbs the crystal quality of the lattice and causes the sputtering of AlGaN. An energy threshold, below which degradations remain limited, has however been demonstrated and tested. The second factor identified is the modified thickness. The greater the modified thickness, the more it has an influence on the electronic channel and its properties. This thickness can be increased by high bombardment energy or by the use of light elements which are deeply implanted in AlGaN. These results then served as a framework for the development of innovative processes in order to limit the damage during GaN etching. We studied three cyclic processes of the ALE type: O2-BCl3, Cl2-Ar and Cl2-He. These studies made it possible to highlight their different self-limiting and selectivity characteristics as well as to propose etching mechanisms models. Characterization and comparison with standard processes have highlighted their performance and in particular their ability to reduce the electrical degradation induced during etching.
Complete list of metadata
Contributor : Abes Star :  Contact
Submitted on : Wednesday, January 19, 2022 - 10:40:10 AM
Last modification on : Friday, March 25, 2022 - 9:43:19 AM


Version validated by the jury (STAR)


  • HAL Id : tel-03052022, version 2



Frédéric Le Roux. Développement de procédés de gravure plasma sans dommage pour l'électronique de puissance à base de GaN. Micro et nanotechnologies/Microélectronique. Université Grenoble Alpes [2020-..], 2020. Français. ⟨NNT : 2020GRALT017⟩. ⟨tel-03052022v2⟩



Record views


Files downloads