Skip to Main content Skip to Navigation
Theses

Procédés de gravure plasma pour la réalisation de structures verticales de diodes Schottky de nouvelle génération à base de GaN

Abstract : Gallium nitride (GaN) is a wide bandgap III-V semiconductor with interesting electrical properties in order to replace Si in the field of power devices. The subject of this thesis was then to study one of the essential steps to realize a GaN based Schottky diode : the etch. The aim was to develop etching processes allowing the realization of an ohmic contact on an embedded GaN n+ layer. They must combine GaN etching performances compatible with industrial requirements and etch profiles and surface states compatible with an ohmic contact. The etching of a 5 to 6 μm GaN layer by four different reactors was studied in order to realize a pseudovertical structure. Plasma and GaN surfaces analyses were performed during and after etching by five developed and optimized processes. These analyses showed that best compromise was obtained for inductive chlorine plasmas with a moderate bias. The creation of a passivation layer which is able to protect GaN surface, thanks to fluorine addition in plasma chemistries was also established. To overcome the etch rate decreases induced by fluorine addition, a time multiplexed etching process, alternating etch and passivation steps, was developed and studied. Researches were also performed to achieve a vertical diode. Etching of 300 μm depth Si vias by standard cryogenic and anisotropic STiGer processes were carried out. A revelation process was also developed in order to study buffer layers etching. Effective buffer etching by chlorine plasma was demonstrated with or without Si vias.
Keywords : GaN Etching Plasma
Complete list of metadatas

Cited literature [365 references]  Display  Hide  Download

https://tel.archives-ouvertes.fr/tel-02003623
Contributor : Abes Star :  Contact
Submitted on : Friday, February 1, 2019 - 12:28:04 PM
Last modification on : Thursday, March 5, 2020 - 6:49:39 PM

File

nicolas-gosset_3163_vd.pdf
Version validated by the jury (STAR)

Identifiers

  • HAL Id : tel-02003623, version 1

Collections

Citation

Nicolas Gosset. Procédés de gravure plasma pour la réalisation de structures verticales de diodes Schottky de nouvelle génération à base de GaN. Physique des plasmas [physics.plasm-ph]. Université d'Orléans, 2016. Français. ⟨NNT : 2016ORLE2076⟩. ⟨tel-02003623⟩

Share

Metrics

Record views

114

Files downloads

76