In this project, we investigated the preparation of a single-crystal Au(100) substrate and explored the growth of ultrathin SnS layers under ultra-high vacuum (UHV) conditions, mainly using scanning tunnelling microscopy (STM) complemented by low-energy electron diffraction (LEED). Surface preparation via repeated cycles of argon ion (Ar+) sputtering and thermal annealing yielded an atomically clean and well-ordered Au(100) reconstructed surface. Subsequently, thermal evaporation of SnS onto the substrate was carried out under various deposition conditions. The LEED and STM characterisations performed after deposition revealed diffraction patterns and surface topographies identical to those of the bare Au(100) surface, with no discernible SnS island nucleation, coverage, or structural modification. This work discussed also the experimental limitations encountered, including measurement noise and the absence of SnS deposition, evaluates potential causes such as source depletion or unoptimized evaporation parameters, and outlines technical adjustments to ensure reliable growth in future work.