Patent ID: 8969712
Filing Date: 2015-03-03
Classification: H01L,Y02E,Y02P

Abstract:
1. A multijunction solar cell comprising: an upper first solar subcell having a first band gap in the range of approximately 1.8 to 2.1 eV; a second solar subcell adjacent to said first solar subcell and having a second band gap smaller than said first band gap and in the range of approximately 1.35 to 1.45 eV; a graded interlayer adjacent to said second solar subcell, said graded interlayer having a third band gap and being composed of (In a third solar subcell adjacent to said graded interlayer, said third subcell having a fourth band gap smaller than said second band gap and in the range of approximately 0.9 to 1.1 eV such that said third subcell is lattice mismatched with respect to said second subcell; a lower fourth solar subcell adjacent to said third solar subcell, said lower fourth subcell having a fifth band gap smaller than said fourth band gap and in the range of approximately 0.6 to 0.8 eV and a high band gap contact layer composed of p++ type InGaAlAs adjacent the lower fourth solar subcell, wherein said graded interlayer is compositionally graded to lattice match the second subcell on one side and the third subcell on the other side, and wherein the upper first subcell is composed of an InGaP