Solar cell with high photoelectric conversion efficiency and method for manufacturing solar cell with high photoelectric conversion efficiency

A method for manufacturing a solar cell, comprising the steps of:

• forming unevenness on both of main surfaces of a semiconductor substrate of a first conductivity type;
• forming a base layer of the first conductivity type, having a dopant concentration higher than in the semiconductor substrate, on a first main surface of the semiconductor substrate;
• forming a diffusion mask on the base layer;
• removing the diffusion mask in a pattern to have a remaining diffusion mask at other than a portion where the diffusion mask have been removed;
• forming an emitter layer of a second conductivity type which is an opposite conductivity type to the first conductivity type, on the portion of the first main surface where the diffusion mask have been removed;
• removing the remaining diffusion mask;
• forming a dielectric film on the first main surface;
• forming a base electrode on the base layer;
• and
• forming an emitter electrode on the emitter layer.

A solar cell comprising:

• a semiconductor substrate of a first conductivity type;
• a base layer of the first conductivity type, having a dopant concentration higher than in the semiconductor substrate, and an emitter layer of a second conductivity type which is an opposite conductivity type to the first conductivity type, each of the layer being provided on a first main surface of the substrate;
• a dielectric film provided on the base layer and the emitter layer;
• a base electrode electrically connected with the base layer;
• and
• an emitter electrode electrically connected with the emitter layer;
• wherein, a surface of the semiconductor substrate is provided with unevenness formed at least at the contact interface between the base electrode and the base layer;
• and
• the first main surface has a recess in a pattern, with the surface of the recess being flat, and the emitter layer is formed on the surface of the recess.