Self-assembled InAs quantum dots (QDs) on In0.52Al0.48As layer lattice matched to (1 0 0) InP substrates have been grown by molecular beam epitaxy (MBE) and evaluated by transmission electron microscopy (TEM) and photoluminescence (PL), TEM observations indicate that defect-free InAs QDs can be grown to obtain emissions over the technologically important 1.3-1.55 mum region. The PL peak positions for the QDs shift to low energy as the InAs coverage increases, corresponding to increase in QD size. The room temperature PL peak at 1.58 mum was observed from defect-free InAs QDs with average dot height of 3.6 nm. (C) 2002 Elsevier Science B.V. All rights reserved.