The process comprises the following steps: (1) forming a glass sheet which defines a substrate layer for the solar cell product; (2) forming a diffusion barrier layer on at least one surface of the substrate; (3) forming a first electrically-conductive layer on the diffusion barrier, the first electrically-conductive layer being a first electrode in the solar cell product; (4) depositing small-grain polycrystalline silicon in a thin film, i.e., 10-100 micrometers, on the first electrode layer; (5) recrystallizing, typically by heating, the deposited polycrystalline silicon until it reforms into large-grain polycrystalline or single-crystal silicon; (6) forming a PN junction in the recrystallized silicon layer; and (7) forming a second electrically-conductive layer on the recrystallized silicon layer, the second electrically-conductive layer being a second electrode in the solar cell product. The solar cell product produced by the above-process may be fabricated in large surface area configurations, suitable for terrestrial as well as extra-terrestrial use, at relatively low cost.