Growth and characterizations of InP self-assembled quantum dots embedded in InAIP grown on GaAs substrates

We report the characteristics of InP self-assembled quantum dots embedded in In0.5Al0.5P on GaAs substrates grown by metalorganic chemical vapor deposition. The InP quantum dots show increased average dot sizes and decreased dot densities, as the growth temperature increases from 475°C to 600°C with constant growth time. Above the growth temperature of 600°C, however, dramatically smaller and densely distributed self-assembled InP quantum dots are formed. The small InP quantum dots grown at 650°C are dislocation-free “coherent” regions with an average size of ∼20 nm (height) and a density of ∼1.5 × 108 mm−2. These InP quantum dots have a broad range of luminescence corresponding to red or organge in the visible spectrum.