Growth and Characterisation of InAs/GaAs Quantum Dots grown by MOCVD

Abstract

InAs/GaAs quantum dots (QDs) were grown by low pressure Metal-Organic Chemical Vapour Deposition in the Stranski-Krastanow growth mode. We describe the influence of growth parameters such as coverage, the V/III ratio, growth temperature and growth interrupts on the QD nucleation and the importance of avoiding formation of larger islands which are particularly susceptible to dislocations. After an extensive study of these growth parameters we are now able to achieve device quality InAs/GaAs QDs with a density of 3×10 10cm-2. Three layers of these QDs have been incorporated into a thin p-clad laser structure which lases from an excited state due to high absorption loss and insufficient ground state gain.