The issues pertaining to non-uniform sputtering from polycrystalline grains in metal thin films during Secondary Ion Mass Spectrometer depth profiling process are investigated. A case study on Mo thin films obtained through magnetron sputter deposition at different substrate temperatures and possessing different microstructural features is presented. X-ray diffraction, scanning electron microscopy, Rutherford backscattering spectrometry and atomic force microscopy were used to elucidate and corroborate the experimental observations of diffusion like broadening observed in the SIMS profiles. While the interfacial diffusion is ruled out based on the inferences derived from complementary experimental investigations, the observed broadening could be attributed to the influence of microstructural features on the sputtering process. (C) 2016 Elsevier B.V. All rights reserved.