Patent ID: 9356176
Filing Date: 2016-05-31
CPC Classification: H01L,Y02E,Y02P

Claim Text:
1. A multijunction solar cell having at least four solar subcells, the multijunction solar cell comprising: a first solar subcell having a first band gap; a first graded interlayer adjacent to the first solar subcell, said first graded interlayer having a second band gap greater than said first band gap and that is constant at 1.5 eV throughout the thickness of the first graded interlayer; and a second solar subcell adjacent to said first graded interlayer, said second solar subcell having a third band gap smaller than the first band gap of the first solar subcell wherein said second solar subcell is lattice mismatched with respect to said first solar subcell; a second graded interlayer adjacent to said second solar subcell, said second graded interlayer having a fourth band gap greater than said third band gap of the second solar subcell and that is constant at 1.1 eV throughout the thickness of the second graded interlayer; and a third solar subcell adjacent to said second graded interlayer, said third solar subcell having a fifth band gap smaller than said third band gap of the second solar subcell wherein said third solar subcell is lattice mismatched with respect to said second solar subcell, wherein each of the first and second graded interlayers is composed, respectively, of a compositionally step-graded series of (In