Electron transport properties in high electron mobility transistor structures improved by V-Pit formation on the AlGaN/GaN interface

0572001 - FZÚ 2024 RIV US eng J - Článek v odborném periodiku
Hospodková, Alice - Hájek, František - Hubáček, Tomáš - Gedeonová, Zuzana - Hubík, Pavel - Hývl, Matěj - Pangrác, Jiří - Dominec, Filip - Košutová, Tereza
Electron transport properties in high electron mobility transistor structures improved by V-Pit formation on the AlGaN/GaN interface.
ACS Applied Materials and Interfaces. Roč. 15, č. 15 (2023), s. 19646-19652. ISSN 1944-8244. E-ISSN 1944-8252
Grant CEP: GA MŠMT(CZ) LTAIN19163; GA ČR(CZ) GF22-28001K; GA MŠMT LM2023051
Institucionální podpora: RVO:68378271
Klíčová slova: HEMT * GaN * AlGaN * metal-organic vapor phase epitaxy * dislocations * electron mobility
Obor OECD: Condensed matter physics (including formerly solid state physics, supercond.)
Impakt faktor: 9.5, rok: 2022
Způsob publikování: Open access

This work suggest new morphology for AlGaN/GaN interface which enhances electron mobility in 2D electron gas (2DEG) of HEMT structures. The widely used technology for preparation of GaN channel in AlGaN/GaN HEMT transistors is the growth at high temperature around 1000°C in hydrogen atmosphere. The main reason for these conditions is the aim to prepare atomically flat epitaxial surface for AlGaN/GaN interface and to achieve layer with the lowest possible carbon concentration. In this work we show, that smooth AlGaN/GaN interface is not necessary for high electron mobility in 2DEG. Surprisingly, when the high temperature GaN channel layer is replaced by the layer grown at temperature 870°C in nitrogen using TEGa as a precursor, the electron Hall mobility increases significantly. This unexpected behavior can be explained by a spatial separation of electrons by V-pits from the regions surrounding dislocation which contain increased concentration of point defects and impurities.
Trvalý link: https://hdl.handle.net/11104/0342845