Why and how In composition fluctuations appear in InGaN? - CNRS - Centre national de la recherche scientifique Accéder directement au contenu
Article Dans Une Revue Journal of Crystal Growth Année : 2023

Why and how In composition fluctuations appear in InGaN?

Pourquoi et comment les fluctuations de composition apparaissent dans InGaN ?

Résumé

We modeled by kinetic Monte Carlo simulations the growth of InGaN alloys on perfectly oriented and misoriented GaN surfaces. As the growth temperature increases, we show that two phenomena occur: composition pulling along the growth direction and lateral indium rich cluster formation. We show that both phenomena have the same origin, strain, and that temperature enables these phenomena to manifest themselves in measurable quantities. Indeed, there is a continuous transition as a function of growth temperature between statistical alloys, described by a binomial distribution law, and heterogeneous layers with indium rich clusters occurring at higher growth temperatures. We quantify this transition by introducing a cluster index based on the In and Ga atom spatial distribution. We show that this cluster index increases above a given temperature, while at low temperature and, in thin layers, it is determined by surface roughness and the associated In fluctuations. Composition pulling can be observed on a larger temperature range. Composition fluctuations are thus caused by strain, and permitted by In mobility at the surface during growth at sufficiently high temperature.
Fichier principal
Vignette du fichier
JCG-hal.pdf (983.19 Ko) Télécharger le fichier
Origine : Fichiers produits par l'(les) auteur(s)

Dates et versions

hal-03902241 , version 1 (16-12-2022)

Identifiants

Citer

Jean-Yves Duboz, Wanda Isnard, Jesus Zúñiga-Pérez, Jeans Massies. Why and how In composition fluctuations appear in InGaN?. Journal of Crystal Growth, 2023, 603, pp.127033. ⟨10.1016/j.jcrysgro.2022.127033⟩. ⟨hal-03902241⟩
41 Consultations
80 Téléchargements

Altmetric

Partager

Gmail Facebook X LinkedIn More