Title :
Wafer bonding for use in mechanically stacked multi-bandgap cells
Author :
Sharps, P.R. ; Timmons, M.L. ; Hills, J.S. ; Gray, J.L.
Author_Institution :
Res. Triangle Inst., Research Triangle Park, NC, USA
fDate :
29 Sep-3 Oct 1997
Abstract :
Two and three junction monolithic two-terminal solar cells have been developed that have 1-Sun, AM0 efficiencies of greater than 25%. In order to reach 1-Sun efficiencies of 30% and greater, solar cells with more junctions are required. Mechanically stacking junctions with different band gaps provides a means of developing such a cell. The authors propose a four-junction, mechanically stacked cascade solar cell structure that projects to a 34.8% AM0 efficiency. Wafer bonding provides a means of mechanically joining semiconductor materials with different lattice constants. They present optical, electrical and mechanical data on wafer bonding GaAs and InP substrates. The data indicate that wafer bonding can be used to develop a four-junction device
Keywords :
III-V semiconductors; energy gap; gallium arsenide; gallium compounds; indium compounds; p-n heterojunctions; semiconductor device testing; solar cells; wafer bonding; 34.8 percent; GaInP-GaAs-InP-GaInAsP-GaInAs; GaInP/GaAs/InP/GaInAsP/GaInAs solar cells; cascade solar cell structure; electrical data; four-junction multi-bandgap solar cells; lattice constants; mechanical data; mechanical stacking; optical data; semiconductor materials; substrates; wafer bonding; Current limiters; Gallium arsenide; Indium phosphide; Lattices; Manufacturing; Photonic band gap; Semiconductor materials; Stacking; Substrates; Wafer bonding;
Conference_Titel :
Photovoltaic Specialists Conference, 1997., Conference Record of the Twenty-Sixth IEEE
Conference_Location :
Anaheim, CA
Print_ISBN :
0-7803-3767-0
DOI :
10.1109/PVSC.1997.654231
