Results of liquid phase epitaxial lateral overgrowth of GaSb layers on GaSb substrates are presented. We show that width to thickness ratio of the layers depends strongly on growth temperature and melt supercooling. Moreover, silicon doping has been found important for successful lateral overgrowth of GaSb layers. At our growth conditions silicon solubility in the melt has been identified as the main factor limiting value of width to thickness ratio of the layers. As the result of presented procedure of growth optimisation, laterally overgrown GaSb epilayers with width to thickness ratio as large as 15 have been obtained. (C) 2003 Elsevier Science B.V. All rights reserved.