The effects of covering InAs quantum dot (QD) layer by InxGa1-xAs thin strain-reducing layer (SRL) on QD properties were studied by photoluminescence (PL) and atomic force microscopy (AFM). Samples were grown by low-pressure metalorganic vapor phase epitaxy. The In content in SRL was changed in the range 0-29%. The red shift of room temperature PL maxima from 1.28 to 1.46 mu m with increasing In content was observed. The energy difference between PL transitions of the ground state and the first excited state (Delta E-SP) was almost unchanged (similar to 85meV) up to 23% of In in SRL. AFM results show an increase of QD height and no change in QD diameter with increasing In content in SRL. This can be the cause of the red shift of emission with increasing concentration of In in SRL and the conservation of Delta E-SP. (c) 2006 Elsevier B.V. All rights reserved.