US 11,056,598 B2
Solar cell
Jungmin Ha, Seoul (KR); Youngho Choe, Seoul (KR); and Changseo Park, Seoul (KR)
Assigned to LG ELECTRONICS INC., Seoul (KR)
Filed by LG ELECTRONICS INC., Seoul (KR)
Filed on Apr. 18, 2019, as Appl. No. 16/388,491.
Application 16/388,491 is a continuation of application No. 13/614,445, filed on Sep. 13, 2012, abandoned.
Claims priority of application No. 10-2012-0014116 (KR), filed on Feb. 13, 2012.
Prior Publication US 2019/0245101 A1, Aug. 8, 2019
Int. Cl. H01L 31/0224 (2006.01); H01L 31/0216 (2014.01); H01L 31/068 (2012.01); H01L 31/0236 (2006.01)
CPC H01L 31/022441 (2013.01) [H01L 31/02168 (2013.01); H01L 31/02363 (2013.01); H01L 31/0684 (2013.01); Y02E 10/547 (2013.01)] 17 Claims
OG exemplary drawing
 
1. A bifacial solar cell comprising:
a substrate formed of a silicon wafer having an n-type conductivity;
an emitter region positioned on a front surface of the substrate and having a p-type conductivity;
a front negative fixed charge layer on the emitter region, and a front positive fixed charge layer on the front negative fixed charge layer;
a plurality of first front electrodes extending in a first direction and connected to the emitter region through the front negative fixed charge layer and the front positive fixed charge layer;
a plurality of second front electrodes extending in a second direction crossing the first direction and electrically and physically connected to the plurality of first front electrodes;
a back aluminum oxide layer and a back silicon nitride layer on a back surface of the substrate;
a plurality of back surface field regions extending in the first direction and locally positioned on the back surface of the substrate;
a plurality of first back electrodes extending in the first direction and directly positioned on the plurality of back surface field regions through the back aluminum oxide layer and the back silicon nitride layer; and
a plurality of second back electrodes extending in the second direction and electrically and physically connected to the plurality of first back electrodes,
wherein the front negative fixed charge layer and the back aluminum oxide layer have the same thickness, and
wherein in the back surface of the substrate positioned between two back surface field regions adjacent to each other in the second direction, a first length of the back surface of the substrate in the first direction is greater than a second length of the back surface of the substrate in the second direction.