Self-assembled GaInNAs quantum dots (QD) with inserted GaAsN strain-reducing layer were grown on GaAs (0 0 1) substrate by solid source molecular beam epitaxy. The highest room temperature photoluminescence (PL) intensity at wavelength of similar to1.57 mum was obtained from the sample grown at 500degreesC, which has the most uniform QD size observed from atomic force microscopy measurement. A number of samples with different spacer thickness and stacked QD layers were grown to investigate the effect of growth condition for GaIn0.5N0.01As QDs. Multilayer structures with 5 QD stacks and spacer layer thickness of 2 nm were found to show the optimum result in terms of PL intensity. (C) 2004 Elsevier B.V. All rights reserved.