Growth and temperature characteristic of self-assembled InAs-QD on GaInP

• Published in: Journal of crystal growth 2003-04, Vol.251 (1), p.223-229
• Main Authors: Amanai, H., Nagao, S., Sakaki, H.
• Format: Article
• Language: English
• Subjects: A3. Molecular beam epitaxy; A3. Quantum dots; A3. Self-assembled; B1. GaInP; B1. InAs; Cross-disciplinary physics: materials science; rheology; Exact sciences and technology; Materials science; Methods of deposition of films and coatings; film growth and epitaxy; Molecular, atomic, ion, and chemical beam epitaxy; Nanoscale materials and structures: fabrication and characterization; Physics
• ISSN: 0022-0248; 1873-5002
• DOI: 10.1016/S0022-0248(02)02426-0

The (Al 1− x Ga x ) 0.5In 0.5P/InAs system has a large band discontinuity and is expected to improve the characteristic temperature of QD lasers by embedding InAs-QD in GaInP. We investigated the QD density and size of InAs-QD deposited on GaInP with various growth conditions, namely InAs growth temperature ( T s=450–500°C) and As-flux (3×10 −7–6×10 −6 mbar) by AFM measurement, and we compared the temperature characteristics of InAs-QD embedded in GaInP with InGaAs-QW in GaInP, InGaAs-QW in GaAs and InAs-QD in GaAs by PL measurement at 10–380 K. The size and total volume of InAs-QD on GaInP increased according to the rise in growth temperature and As-flux, although the amount of deposited InAs was constant. This means that a considerable amount of In was supplied for the QD layer from the GaInP matrix and this was enhanced by the growth temperture and As-flux. Comparing the integrated PL intensity with GaAs/InAs-QD, it was shown that no obvious decline of PL intensity of GaInP/InAs-QD was observed up to around 200 K, though in GaAs/InAs-QD, it began to fall from around 50 K. Moreover, even when comparing with GaAs/InGaAs-QW, the integrated intensity of GaInP/InAs-QD became superior to that of GaAs/InGaAs-QW above room temperature. This result demonstrates that embedding InAs-QD in the GaInP matrix is considerably effective in improving the temperature characteristic of InAs-QD.