The presence of interface recombination in a complex multilayered thin-film solar structure causes a disparity between the internal open-circuit voltage (VOC,in), measured by photoluminescence, and the external open-circuit voltage (VOC,ex) i.e. an additional VOC deficit. Higher VOC,ex value aim require a comprehensive understanding of connection between VOC deficit and interface recombination. Here, a deep near-surface defect model at the absorber/buffer interface is developed for copper indium di-selenide solar cells grown under Cu excess conditions to explain the disparity between VOC,in and VOC,ex. The model is based on experimental analysis of admittance spectroscopy and deep-level transient spectroscopy, which show the signature of deep acceptor defect. Further, temperature-dependent current-voltage measurements confirm the presence of near surface defects as the cause of interface recombination. The numerical simulations show strong decrease in the local VOC,in near the absorber/buffer interface leading to a VOC deficit in the device. This loss mechanism leads to interface recombination without a reduced interface bandgap or Fermi level pinning. Further, these findings demonstrate that the VOC,in measurements alone can be inconclusive and might conceal the information on interface recombination pathways, establishing the need for complementary techniques like temperature dependent current voltage measurements to identify the cause of interface recombination in the devices.
Sood, Mohit, et al. "Near surface defects: Cause of deficit between internal and external open-circuit voltage in solar cells." Progress in Photovoltaics, vol. 30, no. 3, Oct. 2021. https://doi.org/10.1002/pip.3483
Sood, Mohit, Urbaniak, Aleksander, Boumenou, Christian Kameni, Weiss, Thomas Paul, Elanzeery, Hossam, Babbe, Finn, Werner, Florian, Melchiorre, Michele, & Siebentritt, Susanne (2021). Near surface defects: Cause of deficit between internal and external open-circuit voltage in solar cells. Progress in Photovoltaics, 30(3). https://doi.org/10.1002/pip.3483
Sood, Mohit, Urbaniak, Aleksander, Boumenou, Christian Kameni, et al., "Near surface defects: Cause of deficit between internal and external open-circuit voltage in solar cells," Progress in Photovoltaics 30, no. 3 (2021), https://doi.org/10.1002/pip.3483
@article{osti_1827335,
author = {Sood, Mohit and Urbaniak, Aleksander and Boumenou, Christian Kameni and Weiss, Thomas Paul and Elanzeery, Hossam and Babbe, Finn and Werner, Florian and Melchiorre, Michele and Siebentritt, Susanne},
title = {Near surface defects: Cause of deficit between internal and external open-circuit voltage in solar cells},
annote = {The presence of interface recombination in a complex multilayered thin-film solar structure causes a disparity between the internal open-circuit voltage (VOC,in), measured by photoluminescence, and the external open-circuit voltage (VOC,ex) i.e. an additional VOC deficit. Higher VOC,ex value aim require a comprehensive understanding of connection between VOC deficit and interface recombination. Here, a deep near-surface defect model at the absorber/buffer interface is developed for copper indium di-selenide solar cells grown under Cu excess conditions to explain the disparity between VOC,in and VOC,ex. The model is based on experimental analysis of admittance spectroscopy and deep-level transient spectroscopy, which show the signature of deep acceptor defect. Further, temperature-dependent current-voltage measurements confirm the presence of near surface defects as the cause of interface recombination. The numerical simulations show strong decrease in the local VOC,in near the absorber/buffer interface leading to a VOC deficit in the device. This loss mechanism leads to interface recombination without a reduced interface bandgap or Fermi level pinning. Further, these findings demonstrate that the VOC,in measurements alone can be inconclusive and might conceal the information on interface recombination pathways, establishing the need for complementary techniques like temperature dependent current voltage measurements to identify the cause of interface recombination in the devices.},
doi = {10.1002/pip.3483},
url = {https://www.osti.gov/biblio/1827335},
journal = {Progress in Photovoltaics},
issn = {ISSN 1062-7995},
number = {3},
volume = {30},
place = {United States},
publisher = {Wiley},
year = {2021},
month = {10}}