Purpose: The aim of the paper was to apply Sherescan instrument, which is a valuable tool used for fault detection, error diagnosis and process optimization by cell manufacturers, paste suppliers, institutes and universities all over the world.Design/methodology/approach: Screen printed front side contacts and next to co-fired them in the infrared conveyor furnace were carried out at 920°C temperature. A commercial silver paste to form front side metallization was apply into investigations. The investigations were carried out on monocrystalline silicon wafers. Front side metallization of solar cell was formed on textured surface with coated antireflection layer. Investigated were both surface topography and cross section of front contacts using the SEM microscope. The size of textured silicon surface was measured using the AFM microscope. The thickness of tested front contacts was measured using SEM and CLSM microscope. The metal resistance of solar cells was investigated using the ‘Sherescan’ instrument. The I-V characteristics of solar cells were also investigated.Findings: The technological recommendations for the co-firing technology in order to produce a uniformly melted structure, well adhering to the substrate, with the low resistance of the front electrode-to-substrate joint zone.Research limitations/implications: The resistance of the metal-semiconductor connection zone depends on conductive paste composition from which the paths were made, as well as manufacturing conditions.Originality/value: The influence of the obtained front side metallization features on electrical properties of solar cell was estimated.