Area-controlled growth of InAs quantum dots and improvement of density andsize distribution

We propose and demonstrate a scheme (area-controlled growth) for controllin g where self-assembled InAs quantum dots form, using a SiO2 mask and select ive area metalorganic chemical vapor deposition growth. Using this techniqu e, quantum dots can be formed in only selected areas of a growth plane. How ever, in the regions where dots are formed there is variation of dot densit y and size along the mask stripe direction because of the diffusion of spec ies in the vapor phase. We achieve more uniform distributions of dot densit y and size by changing the mask pattern. Using this growth technique, it is possible to fabricate integrated optical devices containing an external re flector together with quantum dots serving as the active layer of a semicon ductor laser. (C) 2000 American Institute of Physics. [S0003-6951(00)03647- 0].