We report the self-assembly of InGaAs quantum dots (QDs) grouped along lines on semiconductor surfaces. Nanoscale spatial thermal modulations were created in-situ on strained-but-flat InGaAs surfaces in a Molecular Beam Epitaxy (MBE) growth chamber by employing interferential irradiations of high power laser pulses. As-irradiated surfaces were examined using an attached ultra-high vacuum Scanning Tunneling Microscope (STM). STM images indicate that the irradiation induces self-assembly of QDs. The average size of laser-induced QDs is smaller while their density is larger than that of QDs formed by the typical Stranski-Krastanov (S-K) growth mode. Furthermore, the dot density is modulated sinusoidally with a periodicity commensurate with that of the interference, which suggests that the placement of QDs can be controlled on the scale of the optical wavelength used. (C) 2012 Elsevier B.V. All rights reserved.