Method for manufacturing a solar cell from a substrate wafer

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

• forming through-holes in a substrate wafer of n-doped, monocrystalline silicon by electrochemical etching a first surface of said substrate wafer to produce a perforated, self-supporting layer of n-doped, monocrystalline silicon;
• producing at least one n-doped region and at least one p-doped region to form a pn-junction in said self-supporting layer, both of said regions adjoining a first principal face of said self-supporting layer, said first principal face being oriented parallel to said first surface,
• said step of producing said at least one p-doped layer including p.sup.+ -doping an entire surface of said first surface of said self-supporting layer to produce a p.sup.+ -doped region so that said pn-junction is formed, whereas said n-doped region comprises an inside of said self-supporting layer;
• producing a mask that covers an entire surface of said first surface of said self-supporting layer except a portion of said first surface in which said n-doped region is to adjoin said first principal face;
• uncovering said first surface of said n-doped region by etching off said p.sup.+ -doped surface not covered by said mask;
• forming a contact to said at least one n-doped region and a contact to said at least one p-doped region on said first principal face for operating said pn-junction as a solar cell into which light is incident via a second principal face lying opposite to said first principal face, including
• providing a respective contact for a p.sup.+ -doped region and said uncovered n-doped region at said first principal face after removal of said mask.