Wide Band Gap Window Layers In Inverted Metamorphic Multijunction Solar Cells

A method of manufacturing a solar cell comprising:

• providing a first semiconductor substrate;
• depositing on a first substrate a sequence of layers of semiconductor material forming a solar cell including a window layer with a bandgap of more than 2.25 eV;
• mounting a surrogate second substrate on top of the sequence of layers;
• and
• removing the first substrate.

A multijunction solar cell comprising:

• a substrate;
• a first solar subcell on said substrate having a first band gap;
• a pseudomorphic window layer disposed over said first subcell having a bandgap greater than that of a lattice matched window layer;
• a second solar subcell disposed over said first subcell and having a second band gap smaller than said first band gap;
• a grading interlayer disposed over said barrier layer and having a third band gap greater than said second band gap;
• and
• a third solar subcell disposed over said grading interlayer that is lattice mismatched with respect to said middle subcell and having a fourth band gap smaller than said third band gap.