a substrate;

a tunnel oxide layer and a doping conductive layer sequentially disposed on a first surface of the substrate in a direction away from the substrate, wherein the tunnel oxide layer includes a silicon oxide material and is doped with nitrogen and phosphorus, wherein a ratio of nitrogen content in the tunnel oxide layer to oxygen content plus the nitrogen content in the tunnel oxide layer is less than 15%, and doping concentration of the phosphorus in the tunnel oxide layer is in a range of 1×10¹⁰/cm³ to 1×10¹⁸/cm³;

a doping surface field disposed in the substrate, wherein the doping surface field is in contact with a side of the tunnel oxide layer facing the substrate, the doping surface field includes a doping element of a same conductivity type as a doping element in the substrate, and wherein, in the doping surface field, a doping concentration on a side of the doping surface field facing the tunnel oxide layer is greater than a doping concentration on a side of the doping surface field away from the tunnel oxide layer, wherein the doping surface field and the doping conductive layer have doping ions of a same conductivity type, and doping concentration of the doping surface field is less than doping concentration of the doping conductive layer, and wherein a thickness of the doping surface field is in a range of 20 nm to 60 nm in a direction from the tunnel oxide layer toward the substrate; and

a metal electrode electrically connected to the doping conductive layer.