FOUR-JUNCTION SOLAR CELL Russian patent published in 2017 - IPC H01L31/328 

FIELD: physics.

SUBSTANCE: four-junction solar cell includes, successively grown on a substrate (1) made of p-Ge, four sub-cells (2), (3), (4), (5), connected to each other by tunnel p-n junctions (6, 7, 8), a metamorphous gradient buffer layer (9) between first (2) and second (3) sub-cells and a contact layer (10). The first sub-cell (2) includes a substrate (1) made of p-Ge, a layer (11) made of n-Ge, a wide-bandgap layer (12) made of n-GalnP and a buffer layer (13) made of n-GaInAs, the second sub-cell (3) includes a layer (14) made of p-GalnAs and a layer (15) made of n-GaInAs, the third sub-cell (4) includes a layer (16) made of p-AIGalnAs and a layer (17) made of n-AlGaInAs, and the fourth sub-cell (5) includes short-period superlattices of A2B6 of p- and n-type (18, 19). The second, third and fourth sub-cells of the multi-junction solar cell are matched on the lattice constant with In_xGa_1-xAs (x=0.25-0.3), and the first (Ge) sub-cell of the multi-junction solar cell is pseudomorphous with the substrate (1) made of p-Ge.

EFFECT: four-junction solar cell is easier to make and has higher bandgap of the upper wide-bandgap sub-cell, which provides high efficiency of converting the short-wave part of solar radiation.

2 ex, 3 dwg