The selective area growth by low-pressure MOVPE using a SiO2 narrow stripe mask array with a wide SiO2 mask at one side of the array was performed for controlling size and density of quantum dots (QDs). To obtain the QD size difference much further, we have tried the 'double-cap' procedure in the selective area growth, and we have successfully controlled the emission from InAs QDs in 75 nm wavelength range on the single chip. (c) 2006 Elsevier B.V. All rights reserved.