METHOD AND DEVICE FOR MANUFACTURING SOLAR CELL

PROBLEM TO BE SOLVED: To obtain a solar cell which provides high photoelectric conversion efficiency by optimizing replacement timing of an alkaline solution used for executing the anisotropic etching.SOLUTION: A silicon (111) substrate is immersed into an etchant, and if the average surface roughness of the pulled-up substrate is 0.5 nm or more, the etchant is replaced. Accordingly, the roughness of the {111} plane of a solar cell to be manufactured is reduced, and defect generation in an amorphous silicon layer due to the roughness and the epitaxial layer formation are suppressed. As a result, defects between the substrate and an amorphous layer boundary face and in a film are reduced, and Voc, FF of a photoelectric conversion element is improved.