2026-06-02T15:02:10Zhttps://docta.ucm.es/rest/oai/request

oai:docta.ucm.es:20.500.14352/1253632025-10-25T00:00:28Zcom_20.500.14352_14col_20.500.14352_15

Electronic transport properties and stability of 2D electron gases on Si3N4/AlOx//KTaO3 heterostructures Santos Solva Junior, Romualdo Martín Merodio, Alejandro Martínez, E. A. Gallego Toledo, Fernando Nemes, Norbert Marcel Bruno, Flavio Yair 538.9 539.124 KTaO3 2DEG Two dimensional electron gas Física del estado sólido Física de materiales Electrónica (Física) 2211.11 Propiedades de Transporte de Electrones 2211 Física del Estado Sólido © Author(s) 2025 2022-5A/IND-24230 We report on the successful stabilization of a two-dimensional electron gas (2DEG) in Si3N4/AlOx//KTaO3(001) heterostructures. Electronic transport measurements reveal that the AlOx layer thickness critically modulates the 2DEG mobility, with an optimal thickness achieving a mobility of μ ≈ 444 cm2 V−1 s−1 at 10 K, which is, despite the amorphous granular nature of the AlOx layers, comparable to epitaxial oxide-based 2DEGs. Thicker AlOx layers reduce mobility and induce a Kondo-like upturn in resistance at low temperatures, which is attributed to oxygen depletion extending into the substrate and enhancing defect scattering. Additionally, the samples remain metallic after six months of exposure to ambient conditions, with high-mobility samples maintaining stable carrier densities and mobilities and experiencing only minor increases in sheet resistance over time. These findings highlight the potential of KTaO3 2DEGs for long-term electronic applications, providing valuable insights for optimizing oxide heterostructures for future device technologies. Comunidad de Madrid Ministetio de Ciencia y Tecnología (España) Agencia Estatal de Investigación (España) European Commission Ministero dell'Università e della Ricerca (Italia) Depto. de Física de Materiales Fac. de Ciencias Físicas TRUE pub 2025-10-24T14:53:22Z 2025-10-24T14:53:22Z 2025-10-22 journal article VoR https://hdl.handle.net/20.500.14352/125363 0021-8979 10.1063/5.0293470 1089-7550 eng info:eu-repo/grantAgreement/AEI/Plan Estatal de Investigación Científica y Técnica y de Innovación 2021-2023/CNS2022-135485/ES/ info:eu-repo/grantAgreement/AEI/Plan Estatal de Investigación Científica y Técnica y de Innovación 2021-2023/TED2021-129254B-C21/ES/ B53D23028580001 R.S. Silva, A.M. Merodio, E.A. Martínez, F. Gallego, N.M. Nemes, and F.Y. Bruno, “Electronic transport properties and stability of 2D electron gases on Si3N4/AlOx//KTaO3 heterostructures,” Journal of Applied Physics 138(16), 165301 (2025). Attribution-NonCommercial 4.0 International http://creativecommons.org/licenses/by-nc/4.0/ open access application/pdf AIP Publishing