NOVELTY - Back contact crystalline semiconductor solar cell comprises a crystalline semiconductor substrate comprising a light receiving frontside surface and a backside surface for forming patterned emitter and base regions; a first electrically conductive metallization layer having an interdigitated pattern of emitter electrodes and base electrodes on the backside surface of the crystalline substrate; an electrically insulating layer attached to the backside surface of the crystalline substrate; and a second electrically conductive metallization layer.    USE - The back contact crystalline semiconductor solar cell is useful in photovoltaics and semiconductor microelectronics.    ADVANTAGE - High-efficiency back-contact crystalline silicon photovoltaic solar cells are provided.    DETAILED DESCRIPTION - Back contact crystalline semiconductor solar cell comprises a crystalline semiconductor substrate comprising a light receiving frontside surface and a backside surface for forming patterned emitter and base regions; a first electrically conductive metallization layer having an interdigitated pattern of emitter electrodes and base electrodes on the backside surface of the crystalline substrate; an electrically insulating layer attached to the backside surface of the crystalline substrate, the electrically insulating layer electrically isolating the first metallization layer from a second electrically conductive metallization layer; and a second electrically conductive metallization layer providing high-conductivity cell interconnections to the first electrically conductive interconnect layer through conductive via plugs formed in the electrically insulating layer, the second electrically conductive interconnect layer having an interdigitated pattern of emitter electrodes and base electrodes. An INDEPENDENT CLAIM is a method for forming a back contact solar cell comprising forming a first layer of electrically conductive metal having an interdigitated pattern of base electrodes and emitter electrodes on the backside surface of crystalline semiconductor substrate, the substrate comprising a light receiving frontside surface and a backside surface for forming patterned emitter and base contacts silicon layer; forming an electrically insulating layer on the first layer of electrically conductive metal, the dielectric layer providing electrical isolation between the first layer of electrically conductive metal and a second layer of electrically conductive metal; forming holes in the electrically insulating layer, the holes providing access to the first layer of electrically conductive metal; and forming a second electrically conductive metallization layer on the electrically insulating layer, the second electrically conductive metallization layer contacting the first electrically conductive metal layer through the holes.