InSb quantum dashes (up to 2.5 x 10(9) cm(-2)) were obtained on an InAs(001) substrate by metalorganic vapor phase epitaxy at T=440 degrees C. A change in the geometry of the InSb nanoislands from a quantum dot to a quantum dash was observed in the dependence on growth conditions. The deposited quantum dashes with average lengths, widths and heights of 300 nm, 100 nm and 30 nm, respectively, were strictly self-oriented by the longer side along the [110] direction. A room-temperature electroluminescence has been observed in type II heterostructures based on the InSb quantum dashes inserted in the unipolar n-InAs matrix. The nanoheterostructures exhibited a positive luminescence (3.62 mu m at 300 K) at either forward or reversed bias, which can be ascribed to interfacial recombination transitions of electrons localized on the InAs side across the type II broken-gap InSb/InAs heterointerface to hole levels of the InSb quantum dashes. (C) 2014 Elsevier B.V. All rights reserved.