Solar cells include bus bars and high aspect-ratio gridlines that are printed on a substrate, and localized melting is induced to slump or flatten the gridline “vertex” portions that are disposed on the bus bars, while maintaining the high aspect-ratio of gridlines portions disposed on the substrate between the bus bars. The localized melting process is induced using one of several disclosed methods, such as rheological melting in which the two printed inks produce a compound that is relatively liquid. Localized melting is also induced using a deliquescing material (e.g., a flux or a solvent film) that is applied to the bus bar or gridline material. Also, eutectic melting is induced using a processing temperature that is between a melting point of the combined gridline/bus bar inks and the individual melting points of the inks alone. Laser-based melting and the use of copolymers is also disclosed.