TY - JOUR

T1 - Ultra-Thin Poly-Si Layers

T2 - Passivation Quality, Utilization of Charge Carriers Generated in the Poly-Si and Application on Screen-Printed Double-Side Contacted Polycrystalline Si on Oxide Cells

AU - Larionova, Yevgeniya

AU - Schulte-Huxel, Henning

AU - Min, Byungsul

AU - Schäfer, Sören

AU - Kluge, Thomas

AU - Mehlich, Heiko

AU - Brendel, Rolf

AU - Peibst, Robby

N1 - Funding information: [ The authors thank R. Winter for the processing of the solar cells. This work was financially supported by the German Federal Ministry for Economic Affairs and Energy (BMWi) under contact number 0324171C (Nextstep) and has also partially received funding from the European Union's Horizon 2020 research and innovation program under grant agreement no 727529 (DISC). The authors thank R. Winter for the processing of the solar cells. This work was financially supported by the German Federal Ministry for Economic Affairs and Energy (BMWi) under contact number 0324171C (Nextstep) and has also partially received funding from the European Union's Horizon 2020 research and innovation program under grant agreement no 727529 (DISC).

PY - 2020/10/6

Y1 - 2020/10/6

N2 - Herein, the various measures to improve the efficiency of large-area screen-printed double-side contacted polycrystalline Si on oxide (POLO)-cells are experimentally demonstrated. The short-circuit current density Jsc increases by 0.6 mA cm−2 upon reducing the thickness of poly-Si from 25 to 10 nm due to the reduction of the parasitic absorption in the poly-Si layer at the textured front side of the cell. Additionally, it is shown for the first time that the minority carriers generated by light absorbed in the poly-Si layer can at least partially be transferred into the crystalline Si base. Remarkably high implied open-circuit voltage Voc,impl values are achieved with n-type cell precursors by introducing an hydrogenation step by AlxOy after reducing the poly-Si thickness, and by an additional annealing step after sputtering of transparent conductive oxides (TCOs). All cell precursors show Voc,impl values of up to 740 mV independent of the poly-Si thickness. A reduction in the open-circuit voltage Voc is observed during back-end processing to 728 mV as measured on the final cells. A certified cell energy conversion efficiency of 22.3% is reported.

AB - Herein, the various measures to improve the efficiency of large-area screen-printed double-side contacted polycrystalline Si on oxide (POLO)-cells are experimentally demonstrated. The short-circuit current density Jsc increases by 0.6 mA cm−2 upon reducing the thickness of poly-Si from 25 to 10 nm due to the reduction of the parasitic absorption in the poly-Si layer at the textured front side of the cell. Additionally, it is shown for the first time that the minority carriers generated by light absorbed in the poly-Si layer can at least partially be transferred into the crystalline Si base. Remarkably high implied open-circuit voltage Voc,impl values are achieved with n-type cell precursors by introducing an hydrogenation step by AlxOy after reducing the poly-Si thickness, and by an additional annealing step after sputtering of transparent conductive oxides (TCOs). All cell precursors show Voc,impl values of up to 740 mV independent of the poly-Si thickness. A reduction in the open-circuit voltage Voc is observed during back-end processing to 728 mV as measured on the final cells. A certified cell energy conversion efficiency of 22.3% is reported.

KW - passivating contacts

KW - polycrystalline silicon

KW - silicon solar cells

KW - transparent conducting oxides

UR - http://www.scopus.com/inward/record.url?scp=85089499844&partnerID=8YFLogxK

U2 - 10.1002/solr.202000177

DO - 10.1002/solr.202000177

M3 - Article

AN - SCOPUS:85089499844

VL - 4

JO - Solar RRL

JF - Solar RRL

IS - 10

M1 - 2000177

ER -