We demonstrated that the growth of InAs on GaAs at rates as low as 0.003 ML/s can be used to form quantum dots (QDs) that are optically active at 1.3 and 1.5 mum. The emission at 1.5 mum (at 300 K) originating from individual InAs QDs embedded in a pure GaAs matrix is close to the important telecom window at 1.55 mum. Such emission is related to a narrow distribution of islands with a height peaked around 15 nm as shown by atomic-force microscopy. (C) 2002 Elsevier Science B.V. All rights reserved.