Comparison of InAs quantum dots grown on GaInAsP and InP

We report on the growth of InAs quantum dots (QDs) on GaInAsP and InP buffers by metal-organic chemical vapour deposition on InP(100) substrates. Indium segregation and the As-P exchange reaction affect the QD nucleation and composition. The As-P exchange reaction has a more pronounced effect on the QDs grown on the InP buffer than on those grown on the GaInAsP buffer. A very thin (0.6 nm) GaAs interlayer grown between the buffer layer and the InAs QD layer consumes segregated indium and minimizes the As/P exchange reaction. Wavelength tuning from 1450 to 1750 nm covering the technologically important 1550 nm wavelength is also achieved for the InAs QDs grown with the thin GaAs interlayer.