EFFICIENT THREE-JUNCTION SOLAR CELL AND MANUFACTURING METHOD THEREFOR

摘要

An efficient three-junction solar cell and a manufacturing method therefor. The efficient three-junction solar cell comprises: a growth substrate (010), having two polished surfaces; a bottom cell (100), formed by a strain-compensated superlattice structure, inversely growing a rear surface of the growth substrate (010), having a first band gap, and having an equivalent lattice constant matching a lattice constant of the growth substrate (010); a medium cell (200), growing on a front surface of the growth substrate (010), and having a second band gap greater than the first band gap and a lattice constant matching that of the growth substrate (010); a top cell (300), formed above the medium cell (200), and having a third band gap greater than the second band gap and a lattice constant matching the lattice constant of the medium cell (200). Such an energy band gap distribution of the three-junction solar cell meets optimal selection for capturing solar spectrum, and current matching and lattice matching are achieved, thereby effectively improving the photoelectric conversion efficiency of the three-junction solar cell. The manufacturing method therefor uses the method of growing on the two surfaces of the growth substrate, so as to eliminate the complicated process incurred by late inverse growth, thereby increasing the yield.