Edward D Gagnon

US Patent:

20110287578, Nov 24, 2011

Filed:

May 24, 2010

Appl. No.:

12/800824

Inventors:

Steven J. Wojtczuk - Lexington MA, US
Philip T. Chiu - Arlington MA, US
Xuebing Zhang - Nashua NH, US
Edward Gagnon - Bedford MA, US
Michael Timmons - Durham NC, US

International Classification:

H01L 33/02
H01L 33/30

US Classification:

438 94, 257E33005, 257E33023

Abstract:

A method of fabricating on a semiconductor substrate bifacial tandem solar cells with semiconductor subcells having a lower bandgap than the substrate bandgap on one side of the substrate and with subcells having a higher bandgap than the substrate on the other including, first, growing a lower bandgap subcell on one substrate side that uses only the same periodic table group V material in the dislocation-reducing grading layers and bottom subcells as is present in the substrate and after the initial growth is complete and then flipping the substrate and growing the higher bandgap subcells on the opposite substrate side which can be of different group V material.

US Patent:

20150099324, Apr 9, 2015

Filed:

Oct 6, 2014

Appl. No.:

14/507607

Inventors:

- Irvine CA, US
Philip T. Chiu - Arlington MA, US
Xuebing Zhang - Acton MA, US
Edward Gagnon - Bedford MA, US
Michael Timmons - Durham NC, US

International Classification:

H01L 31/18
H01L 31/0687
H01L 31/0693
H01L 31/068

US Classification:

438 74

Abstract:

A method of fabricating on a semiconductor substrate bifacial tandem solar cells with semiconductor subcells having a lower bandgap than the substrate bandgap on one side of the substrate and with subcells having a higher bandgap than the substrate on the other including, first, growing a lower bandgap subcell on one substrate side that uses only the same periodic table group V material in the dislocation-reducing grading layers and bottom subcells as is present in the substrate and after the initial growth is complete and then flipping the substrate and growing the higher bandgap subcells on the opposite substrate side which can be of different group V material.