Metastable cubic SnS phase (pi-SnS) is an emerging material having attractive properties for solar cell applications. In this study, we have investigated the thermal evaporation process of SnS with substrate temperatures of 250-350 degrees C, and have observed the formation of pi-SnS together with the stable orthorhombic phase (alpha-SnS) for the first time by using only SnS as a starting material. X-ray diffraction analysis shows that a single-phase alpha-SnS film is obtained at 350 degrees C, and the fraction of pi-SnS increases with decreasing the substrate temperature to 250 degrees C. The grain shape of the SnS film grown at 250 degrees C observed by scanning electron microscopy was more isotropic than 350 degrees C, consistent with the cubic lattice of pi-SnS. Electrical characterization by Hall measurement reveals the existence of the maximum point of carrier density as a function of substrate temperature, which is understood by the competition between the increases of crystal defects and the fraction of wider-gap pi-SnS than alpha-SnS with decreasing substrate temperature. The formation of pi-SnS brings about lowering of absorption coefficients below the absorption edge of pi-SnS, which are analyzed from transmittance and reflectance spectra. The reason of pi-SnS formation is discussed by comparing the conditions of film deposition with previous reports. (C) 2017 Elsevier B.V. All rights reserved.