Work

Ammonia source molecular beam epitaxy of ScAlN/GaN HEMTs with AlN exclusion layers

Year: 2026

Type: article

Abstract: In this work, ScAlN/GaN high electron mobility transistor heterostructures were grown by molecular beam epitaxy with an ammonia source. The impact of inserting an AlN exclusion layer between the ScAlN barrier and the GaN channel is studied. On the one hand, increasing the AlN exclusion layer thickness from 0.15 to 3.5 nm results in an enhancement of the electron mobility from 391 to 921 cm2/V s. On the other hand, the heterostructure containing a 1.5 nm thick AlN layer grown at 800 °C exhibits a mobility of 666 cm2/V s, while that with a 1.6 nm AlN layer grown at a lower temperature reveals a mobility of 1025 cm2/V s, the maximum recorded in this study, which underlines the important role of this parameter.

Source: Applied Physics Letters

DOI: 10.1063/5.0325373

Authors: Florian Bartoli, Valentina Gallardo-Mödinger, Ileana Florea, Sébastien Chenot, Maxime Hugues, Yvon Cordier

Institutions: Centre National de la Recherche Scientifique, Université Côte d'Azur, Centre de Recherche sur l'Hétéro-Epitaxie et ses Applications

Language: English

Topic: GaN-based semiconductor devices and materials

Subfield: Condensed Matter Physics

Field: Physics and Astronomy

Domain: Physical Sciences

Open Access status: green

Funders: Agence Nationale de la Recherche, H2020 Industrial Leadership

Awards: Réseau national sur GaN, Towards the co-integration of high frequency devices on epitaxial ScAlN, G6921877442