Stress and doping analysis of low n-doped GaN layers on various substrates by micro-Raman mapping
Year: 2026
Type: article
Abstract: In this work, using micro-Raman spectroscopy mapping, we propose a methodology to separate the stress effect from the n-doping effect on A1LO and E2H GaN phonon modes frequency for low n-doped (<1017 cm−3) GaN layers grown on various substrates (GaN, sapphire, and silicon). This methodology shows a linear relation between the two phonon modes, in which the slope corresponds to GaN biaxial stress coefficients ratio KA1LOB/KE2HB and is 0.76 ± 0.01. Our value may act as a useful guideline for selecting or refining KE2HB and KA1LOB values. Samples that are mainly biaxially stressed show good agreement with the linear relation independently of the substrate. As for GaN/GaN samples, the change of slope indicates that layers are predominantly under dislocation-induced stress. However, independently of the substrate, the y-intercept increases with the n-carrier concentration, which provides a qualitive estimation of the net doping.
Source: Applied Physics Letters
DOI: 10.1063/5.0325369
Authors: Ndembi Ignoumba-Ignoumba, Camille Sonneville, Thomas Kaltsounis, Vishwajeet Maurya, Hala El Rammouz, Mohammed El Amrani, Maroun Dagher, Florian Bartoli, Thibaud Guillemin, Adrien Bidaud, Eric Frayssinet, Farid Medjdoub, Hassan Maher, Jean Marie Bluet, Dominique Planson, Julien Buckley, Yvon Cordier, Matthew Charles, Cyril Buttay
Institutions: Lyon 1 Université, École Centrale de Lyon, Centre National de la Recherche Scientifique, Institut National des Sciences Appliquées de Lyon, Commissariat à l'Énergie Atomique et aux Énergies Alternatives, CEA Grenoble, Laboratoire d'Électronique des Technologies de l'Information, Université Grenoble Alpes, Université de Lyon, Institut des Nanotechnologies de Lyon, Université Côte d'Azur, Centre de Recherche sur l'Hétéro-Epitaxie et ses Applications, Institut d'Electronique, de Microélectronique et de Nanotechnologie, Université de Sherbrooke, Laboratoire Nanotechnologies et Nanosystèmes
Language: English
Subfield: Condensed Matter Physics
Field: Physics and Astronomy
Domain: Physical Sciences
Open Access status: green
Funder: Agence Nationale de la Recherche
OpenAlex ID: W7140274471