Effects of Sb incorporation in GaAsSb-capping layer on the optical properties of InAs/GaAs QDs grown by Molecular Beam Epitaxy. (January 2017)

• Record Type: Journal Article
• Authors: Salhi, A.; Alshaibani, S.; Alhamdan, M.; Albrithen, H.; Alyamani, A.; El-Desouki, M.
• Is Part Of: Superlattices and microstructures. Volume 101(2017)
• Page Start: 138
• Page End: 143
• Publication Date: 2017-01
• Subjects: Superlattices as materials -- Periodicals; Microstructure -- Periodicals; Semiconductors -- Periodicals; Superréseaux -- Périodiques; Microstructure (Physique) -- Périodiques; Semiconducteurs -- Périodiques; 621.38152
• DOI: 10.1016/j.spmi.2016.11.021
• Languages: English
• ISSNs: 0749-6036

Abstract

Abstract: We have investigated the effect of antimony incorporation in GaAsSb as a capping layer on the optical properties of InAs quantum dots grown by Molecular Beam Epitaxy. Atomic Force Microscopy (AFM), High Resolution X-Ray Diffraction (HRXRD), photoluminescence (PL) and power dependent PL at 77 K and 300 K have been used for the characterization of the grown samples. Our analysis showed that the emission wavelength increases with Sb content and reaches ∼1.5 μm for Sb concentration of 22%. To achieve this wavelength, a reduction of the growth temperature of the GaAsSb layer from 500 °C to 440 °C was necessary. The wavelength increase is accompanied by a transition from a type I to type II band alignment and a broadening of the PL spectrum to a value of ∼237 nm for an excitation power of 100 mW. This broadening is attributed to the QD size inhomogeneity increase and Sb atoms redistribution during the in-situ annealing during the growth of the barriers at elevated temperature. Our results show the potential of the InAs/GaAsSb system in the development of broadband light sources and super-luminescent light emitting diodes in 1.2–1.5 μm wavelength range. Highlights: InAs capped with GaAsSb strain reducing layer with different Sb content grown by MBE. PL and power dependent PL at 77 K and 300 K have been studied in InAs/GaAsSb system. Emission wavelength extended to 1.5 μm for Sb content of 22% accompanied with transition from type I to type II. Broadening of the PL spectrum for high Sb content.