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Metallization processes are the main major efficiency-limit and cost-determining steps in solar cell processing (crystalline as well as thin film cells).Metallization is essential for extraction of current from the solar cells,in crystalline cells the screen printed metallization patterns,show high metal content,decrease the active cell area too much,have non-zero contact resistance to the cell,decreases cell efficiency and the cell breakage during metallization can reach even 5% adding substantial costs to the photovoltaic generated power.While in thin film cells the conventional TCOs suffer from poor properties,are brittle and expensive.We have developed materials and technologies to replace screen printing processes and TCOs for solar cells.An ink-jet metallization process replacing the screen printing metallization process is enabled by proper inks based on nano silver particles.Taking advantages of the enhanced properties of nano materials as well as all the features of ink-jet printing:digital non-contact printing,high accuracy,narrow pattern printing,high material efficiency (drop on demand concept),high throughput and robust printing.Suitable inks for ink-jet conductive printing can be feasible only through nano metal particles as the inks require very low viscosities and high metal contents.A coating process to form a transparent conductive layer based on nano wires shows promising properties.The extensive research and development work been presented in this paper will show single crystal nano silver particles formulated into very stable,high metal concentration and low viscosity ink-jet inks even with very low surfactant concentrations showing enhanced electrical properties,very low contact resistances and enhanced cell efficiencies.These specially designed nano silver inks are enabling the ink-jet printing metallization process.Nano wire transparent conductive coated layers properties will also be presented.