The InAs quantum dots on GaAs (0 0 1) substrate were first grown by LP-MOVPE using tertiarybutylarsine (TBA) in nitrogen ambient. Samples were characterized using atomic force microscope (AFM) and photoluminescence (PL) spectroscopy at 77 K. The average diameter of the dots increases with the group III source trimethylindium (TMIn) inlet flow. The shape of dots also changes with the TMIn inlet flow. The shape of dots changes from oval to circle, respectively, when the TMIn inlet flow was changed from 60 to 80sccm. When TMI was set at 100sccm, the shape of InAs quantum dots is tetrahedron with two {1 4 14} facets and one {1 1 14} facet and their edges were parallel to [140] and [110] directions, respectively. The dot density is (1.5-2.5) x 10(10)cm(-2). The PL emission from the quantum dots is centered at 1071 nm wavelength and has a full width at half maximum PL spectrum of 55 meV. (C) 2004 Elsevier B.V. All rights reserved.