Millimeter-sized single crystals of CaB6 are obtained by the reaction of B and Ca under 1 GPa and 950-1150 C The structure chemical composition and morphologies of the crystals are characterized by X-ray diffraction and field emission scanning electron microscopy with energy dispersion spectrometry Investigation of the growth mechanism of CaB6 single crystals indicates that the growth temperature affects the shape of the crystals Electric resistivity dependence tests of temperatures from 2 to 300 K show that CaB6 single crystals are conductive materials with semi-metallic behaviors (C) 2010 Elsevier B V All rights reserved