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

Abstract

We report the characteristics of InP self-assembled quantum dots embedded in In/sub 0.5/Al/sub 0.5/P on GaAs substrates and In/sub x/Al/sub 1-x/P self-assembled quantum dots on GaP substrates grown by metalorganic chemical vapor deposition. InP quantum dots show increased average dot sizes and decreased dot densities, as the 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 size of /spl sim/20 nm (height) and a density of /spl sim/1.5/spl times/10/sup 8/ mm/sup -2/. These InP quantum dots have broad range of luminescence corresponding to red or orange in the visible spectrum. InAlP quantum dots on GaP have smaller sizes and higher densities than InP dots on In/sub 0.5/Al/sub 0.5/P.