InP and InAlP self-assembled quantum dots grown by metalorganicchemical vapor deposition

摘要

We report the characteristics of InP self-assembled quantum dotsembedded in In_0.5Al_0.5P on GaAs substrates and In_xAl_1-xP self-assembled quantum dots on GaPsubstrates grown by metalorganic chemical vapor deposition. InP quantumdots show increased average dot sizes and decreased dot densities, asthe growth temperature increases from 475C to 600C. At 650C, however,dramatically smaller and densely distributed quantum dots are formed.The InP quantum dots grown at 650C are dislocation-free“coherent” self-assembled quantum dots with an average sizeof ~20 nm (height) and a density of ~1.5×108 mm-2. These InP quantum dots have broad range of luminescencecorresponding to red or orange in the visible spectrum. InAlP quantumdots on GaP have smaller sizes and higher densities than InP dots on In_0.5Al_0.5P