Method of manufacturing a solar cell by texturing a principal surface using an alkaline solution

1. A method of manufacturing a solar cell including a substrate made of a crystalline semiconductor material, comprising:

depositing a p-type semiconductor layer containing boron on at least part of a first principal surface of the substrate, thereby protecting the at least part of the first principal surface to a subsequent etching or washing step;

etching or washing at least part of a second principal surface of the substrate by subjecting the at least part of the second principal surface to a treatment with an aqueous alkaline solution;

patterning the p-type semiconductor layer by removing a part of the p-type semiconductor layer after the treatment with the aqueous alkaline solution; and

forming electrodes on the pattered p-type semiconductor layer and on an exposed area that is exposed through the removed part of the p-type semiconductor layer, respectively, and

forming a semiconductor junction,

wherein

the semiconductor junction forming step comprises:

removing the p-type semiconductor layer; and

forming a new semiconductor layer containing boron at a lower concentration than that in the p-type semiconductor layer, on the first principal surface to form the semiconductor junction, after the removing step.

2. The method according to claim 1 , wherein the etching or washing step is a step of anisotropically etching the at least part of the second principal surface of the substrate with the aqueous alkaline solution.

3. The method according to claim 1 , wherein the solar cell is a back contact solar cell.

4. The method according to claim 1 , wherein silicon nitride film is not used to protect the substrate from the etching or washing step.

5. A method of manufacturing a solar cell including a substrate made of a crystalline semiconductor material, comprising:

depositing a p-type amorphous silicon layer containing boron on at least part of a first principal surface of the substrate, thereby protecting the at least part of the first principal surface to a subsequent etching or washing step;

etching or washing at least part of a second principal surface of the substrate by subjecting the at least part of the second principal surface to a treatment with an aqueous alkaline solution; and

patterning the p-type amorphous silicon layer by removing a part of the p-type amorphous silicon layer after the treatment with the aqueous alkaline solution; and

forming electrodes on the pattered p-type amorphous silicon layer and on an exposed area that is exposed through the removed part of the p-type amorphous silicon layer, respectively; and

forming a semiconductor junction,

wherein the semiconductor junction forming step comprises:

removing the p-type amorphous silicon layer; and

forming a new semiconductor layer on the first principal surface to form the semiconductor junction, after the removing step,

wherein

the new semiconductor layer contains boron, and

a boron concentration in the new semiconductor layer is lower than a boron concentration in the p-type amorphous silicon layer.

6. The method according to claim 5 , wherein the etching or washing step is a step of anisotropically etching the at least part of the second principal surface of the substrate with the aqueous alkaline solution.

7. The method according to claim 5 , wherein the solar cell construction is a back contact solar cell.

8. The method according to claim 5 , wherein silicon nitride film is not used to protect the substrate from the etching or washing step.