UVA and UVB light emitting diodes with AlyGa1-yN quantum dot active regions covering the 305-335 nm range - Université Nice Sophia Antipolis Accéder directement au contenu
Article Dans Une Revue Semiconductor Science and Technology Année : 2018

UVA and UVB light emitting diodes with AlyGa1-yN quantum dot active regions covering the 305-335 nm range

Bernard Gil
  • Fonction : Auteur correspondant
  • PersonId : 995090

Connectez-vous pour contacter l'auteur

Résumé

Ultra-violet (UV) light emitting diodes (LEDs) using III-N quantum dot (QD) active regions have been fabricated by molecular beam epitaxy on (0001)-oriented sapphire substrates. By using the epitaxial compressive stress between the QD material and the template/barrier layers, leading to a 2D-3D growth mode transition, self-assembled QDs with a nominal Al composition of 10% and 20% have been fabricated on A(10.6)Ga(0.4)N. Atomic force microscopy and transmission electron microscopy measurements show high QD densities, ranging between 2 x 10(11)-5 x 10(11) cm(-2), and height and diameter distributions between 1.5-3 nm and 5-20 nm. LED structures including two different AlyGa1-yN/Al0.6Ga0.4N (0001) QD active regions have then been fabricated and processed using a standard planar geometry and squared mesa structures. Current voltage characteristics and electroluminescence (EL) measurements have been performed at room temperature. In particular, the EL properties are investigated in terms of spectral range and wavelength shift as a function of the injection current density. Typically, an emission between 325 and 335 nm is obtained for Al0.2Ga0.9N QDs and between 305 and 320 nm for Al0.2Ga0.8N QDs. The LED characteristics (EL wavelength and broadening) are then correlated to the QD structural properties and the results, supported by calculations, show the main influence of the QD height dispersion and composition fluctuations. Finally, the light output intensity variation as a function of the injection current density has also been investigated and is discussed in terms of injection and recombination mechanisms in the devices.

Mots clés

Fichier principal
Vignette du fichier
UVA and UVB light emitting diodes with AlyGa1-yN quantum dot active regions covering the 305 nm – 335 nm range.pdf (1.01 Mo) Télécharger le fichier
Origine : Fichiers produits par l'(les) auteur(s)

Dates et versions

hal-01863551 , version 1 (26-01-2022)

Identifiants

Citer

Julien Brault, M. Al Khalfioui, Samuel Matta, B. Damilano, Mathieu Leroux, et al.. UVA and UVB light emitting diodes with AlyGa1-yN quantum dot active regions covering the 305-335 nm range. Semiconductor Science and Technology, 2018, 33 (7), pp.075007. ⟨10.1088/1361-6641/aac3bf⟩. ⟨hal-01863551⟩
121 Consultations
68 Téléchargements

Altmetric

Partager

Gmail Facebook X LinkedIn More