NOVELTY - A multifunction solar cell comprises: an upper first solar subcell; a second solar subcell; a first graded interlayer; a third solar subcell; a second graded interlayer; and a lower fourth solar subcell.    USE - The multifunction solar cell is useful for converting solar energy into electrical energy.    ADVANTAGE - The multifunction solar cell has greater and efficient energy conversion.    DETAILED DESCRIPTION - A multifunction solar cell comprises: an upper first solar subcell having a first band gap; a second solar subcell adjacent to the first solar subcell and having a second band gap smaller than the first band gap; a first graded interlayer adjacent to the second solar subcell; the first graded interlayer having a third band gap greater than the second band gap; and a third solar subcell adjacent to the first graded interlayer, the third subcell having a fourth band gap smaller than the second band gap such that the third subcell is lattice mismatched with respect to the second subcell; a second graded interlayer adjacent to the third solar subcell; the second graded interlayer having a fifth band gap greater than the fourth band gap; and a lower fourth solar subcell adjacent to the second graded interlayer, the lower subcell having a sixth band gap smaller than the fourth band gap such that the fourth subcell is lattice mismatched with respect to the third subcell. An INDEPENDENT CLAIM is a method of manufacturing the solar cell comprising: providing a first substrate; forming an upper first solar subcell having a first band gap on the first substrate; forming a second solar subcell adjacent to the first solar subcell and having a second band gap smaller than the first band gap; forming a first graded interlayer adjacent to the second solar subcell; the first graded interlayer having a third band gap greater than the second band gap; forming a third solar subcell adjacent to the first graded interlayer, the third subcell having a fourth band gap smaller than the second band gap such that the third subcell is lattice mismatched with respect to the second subcell; forming a second graded interlayer adjacent to the third solar subcell; the second graded interlayer having a fifth band gap greater than the fourth band gap; forming a lower fourth solar subcell adjacent to the second graded interlayer, the lower subcell having a sixth band gap smaller than the fourth band gap such that the fourth subcell is lattice mismatched with respect to the third subcell; mounting a surrogate substrate on top of fourth solar subcell; and removing the first substrate.    DESCRIPTION OF DRAWING(S) - The drawing shows a cross-sectional view of the solar cell.    Contact layer (104)    Window layer (105)    Metal layer (130)    Adhesive (131, 513)    Surrogate substrate (132)    Grid lines (501)    Entire channel (510)    Channel (511)    Peripheral portion (512)    Cover glass (514)