Titre :

Vertical leakage in GaN-on-Si stacks investigated by a buffer decomposition experiment

Auteur(s) :

Tajalli, Alaleh [Auteur]
Department of Information Engineering [Padova] [DEI]
Borga, Matteo [Auteur]
Department of Information Engineering [Padova] [DEI]
Meneghini, Matteo [Auteur]
Department of Information Engineering [Padova] [DEI]
de Santi, Carlo [Auteur]
Department of Information Engineering [Padova] [DEI]
Benazzi, Davide [Auteur]
Department of Information Engineering [Padova] [DEI]
Besendörfer, Sven [Auteur]
Fraunhofer Institute for Integrated Systems and Device Technology [Fraunhofer IISB]
Püsche, Roland [Auteur]
Meneghesso, Gaudenzio [Auteur]
Department of Information Engineering [Padova] [DEI]
Derluyn, Joff [Auteur]
Degroote, Stefan [Auteur]
Germain, Marianne [Auteur]
Kabouche, Riad [Auteur]
Institut d’Électronique, de Microélectronique et de Nanotechnologie - UMR 8520 [IEMN]
Abid, Idriss [Auteur]
Institut d’Électronique, de Microélectronique et de Nanotechnologie - UMR 8520 [IEMN]
Meissner, Elke [Auteur]
Fraunhofer Institute for Integrated Systems and Device Technology [Fraunhofer IISB]
Zanoni, Enrico [Auteur]
Institut d’Électronique, de Microélectronique et de Nanotechnologie - UMR 8520 [IEMN]
Department of Information Engineering [Padova] [DEI]
Medjdoub, Farid [Auteur]
WIde baNd gap materials and Devices - IEMN [WIND - IEMN]
Institut d’Électronique, de Microélectronique et de Nanotechnologie - UMR 8520 [IEMN]

Titre de la revue :

Micromachines

Pagination :

101, 9 pages

Éditeur :

MDPI

Date de publication :

2020-01-17

ISSN :

2072-666X

Mot(s)-clé(s) en anglais :

Gallium nitride (GaN) high-electron-mobility transistors (HEMTs)
vertical breakdown voltage
buffer trapping effect

Discipline(s) HAL :

Sciences de l'ingénieur [physics]/Micro et nanotechnologies/Microélectronique

Résumé en anglais : [en]

We investigated the origin of vertical leakage and breakdown in GaN-on-Si epitaxial structures. In order to understand the role of the nucleation layer, AlGaN buffer, and C-doped GaN, we designed a sequential growth ...
Lire la suite >We investigated the origin of vertical leakage and breakdown in GaN-on-Si epitaxial structures. In order to understand the role of the nucleation layer, AlGaN buffer, and C-doped GaN, we designed a sequential growth experiment. Specifically, we analyzed three different structures grown on silicon substrates: AlN/Si, AlGaN/AlN/Si, C:GaN/AlGaN/AlN/Si. The results demonstrate that: (i) the AlN layer grown on silicon has a breakdown field of 3.25 MV/cm, which further decreases with temperature. This value is much lower than that of highly-crystalline AlN, and the difference can be ascribed to the high density of vertical leakage paths like V-pits or threading dislocations. (ii) the AlN/Si structures show negative charge trapping, due to the injection of electrons from silicon to deep traps in AlN. (iii) adding AlGaN on top of AlN significantly reduces the defect density, thus resulting in a more uniform sample-to-sample leakage. (iv) a substantial increase in breakdown voltage is obtained only in the C:GaN/AlGaN/AlN/Si structure, that allows it to reach V BD > 800 V. (v) remarkably, during a vertical I-V sweep, the C:GaN/AlGaN/AlN/Si stack shows evidence for positive charge trapping. Holes from C:GaN are trapped at the GaN/AlGaN interface, thus bringing a positive charge storage in the buffer. For the first time, the results summarized in this paper clarify the contribution of each buffer layer to vertical leakage and breakdown.Lire moins >

Langue :

Anglais

Vulgarisation :

Non

Projet Européen :

Innovative Reliable Nitride-based Power Devices

Collections :

• Institut d'Électronique, de Microélectronique et de Nanotechnologie (IEMN) - UMR 8520

Source :

Harvested from HAL