Anomalous Temperature-Dependent Bimodal Size Evolution of InAs Quantum Dots on Vicinal GaAs(100) Substrates

摘要

Temperature-dependent bimodal size evolution of InAs quantum dots on vicinal GaAs(100) substrates grown by metalorganic chemical vapor deposition (MOCVD) is studied. An abnormal trend of the evolution on temperature is observed. With the increase of the growth temperature, while the density of the large dots decreases continually, that of the small dots first grows larger when temperature was below 520°C, and then there is a sudden decrease at 535°C. Photoluminescence (PL) studies show that QDs on vicinal substrates have a narrower PL line width, a longer emission wavelength and a larger PL intensity.