| 主权项 |
1. A solar cell comprising:
a base region including an active junction, said base region comprising a first side and a second side opposed from said first side; an intrinsic region directly contacting said first side of said base region; an emitter region located on said first side of said base region and directly contacting said intrinsic region such that said intrinsic region is located between said base region and said emitter region; a delta doping layer directly contacting said second side of said base region, said delta doping layer comprising a dopant selected from the group consisting of carbon, silicon, germanium, tin, lead and combinations thereof, wherein said delta doping layer comprises an average layer thickness ranging from about 5 nanometers to about 15 nanometers, wherein said delta doping layer comprises said dopant at a concentration of at least 1×1019 atoms per cm3; and a back surface field layer comprising AlGaAs or AGaInP, said back surface field layer directly contacting a surface of said delta doping layer opposite said base region such that said delta doping layer is disposed directly contacting and between said base region and said back surface field layer. |
