Patent Number: 6,166,320

Title: Tandem solar cell

Abstract: A solar cell that is capable of having a thickness optimum for the highest photoelectric conversion efficiency and achieves reduction of carrier recombination loss is provided. For this purpose, a solar cell (10) is formed by stacking a top cell (12) including an n.sup.+ layer, a p layer, and a p.sup.+ layer, and a bottom cell (14) including an n.sup.+ layer and a p.sup.+ layer arranged at the bottom of the p layer along the back surface. The top cell (12) has a band gap wider than that of the bottom cell (14). A top electrode (18) is formed at the n.sup.+ layer of the top cell (12), while a negative electrode (26) and a positive electrode (28) are individually connected to the n.sup.+ layer and the p.sup.+ layer of the bottom cell (14), respectively. These negative and positive electrodes (26, 28) serve as a pair of electrodes of the bottom cell (14) and the positive electrode (28) is also used as the other electrode of the top cell (12), forming a pair with the top electrode (18) which is one electrode of the top cell (12). As a result, the minority carriers generated in the top and bottom cells (12, 14) can be individually obtained from the electrodes of the respective cells where they are generated.

Inventors: Nagashima; Tomonori (Susono, JP), Nishikawa; Takeshi (Shizuoka-ken, JP)

Assignee: Toyota Jidosha Kabushiki Kaisha

International Classification: H01L 31/06 (20060101); H01L 31/04 (20060101); H01L 31/078 (20060101); H01L 031/04 (); H01L 031/078 ()

Expiration Date: 12/26/2017