TY - JOUR
T1 - Improved hydrogenated amorphous silicon thin-film solar cells realized by replacing n-type Si layer with PFN interfacial layer
AU - Ryu, Seung Yoon
AU - Seo, Ji hoon
AU - Hafeez, Hassan
AU - Song, Myungkwan
AU - Shin, Jun Young
AU - Kim, Dong Hyun
AU - Jung, Yong Chan
AU - Kim, Chang Su
N1 - Publisher Copyright:
© 2017 Elsevier B.V.
PY - 2017/6/1
Y1 - 2017/6/1
N2 - Improvement in the device performance of hydrogenated amorphous silicon (a-Si:H) thin-film solar cells (TFSCs) without hazardous doping gases and complex processes has been a long-standing aim for many researchers. In this work, we replaced the n-type Si layer in an a-Si:H TFSC with an interfacial dipole layer of conjugated polymer electrolyte material, poly [(9,9-bis(3'-(N,N-dimethylamino) propyl)-2,7-fluorene)-alt-2,7-(9,9-dioctylfluorene) (PFN), while keeping the conventional layer scheme. The addition of PFN eliminated the process complexity, improved the device performance, and generated a built-in potential (Vbi) across the p-type Si layer. The power conversion efficiency of the optimized device reached a maximum of 7.17%, which is significant when using a toxicant-free layer. The open-circuit voltage was improved to 0.80 V from 0.47 V in comparison to a reference a-Si:H TFSC without PFN, and the stability in light and dark conditions were greatly enhanced. The fill factor was increased from 0.45 to 0.59 because of the enhancement in shunt/series resistance. The improvement in device performance is mainly due to the creation of an interfacial dipole by the PFN layer, which generated the Vbi across the p-type Si layer, decreased the potential barrier between the i-Si layer and aluminum cathode, and consequently reduced the defects resulting from the coating of the i-Si layer and enhanced electron extraction.
AB - Improvement in the device performance of hydrogenated amorphous silicon (a-Si:H) thin-film solar cells (TFSCs) without hazardous doping gases and complex processes has been a long-standing aim for many researchers. In this work, we replaced the n-type Si layer in an a-Si:H TFSC with an interfacial dipole layer of conjugated polymer electrolyte material, poly [(9,9-bis(3'-(N,N-dimethylamino) propyl)-2,7-fluorene)-alt-2,7-(9,9-dioctylfluorene) (PFN), while keeping the conventional layer scheme. The addition of PFN eliminated the process complexity, improved the device performance, and generated a built-in potential (Vbi) across the p-type Si layer. The power conversion efficiency of the optimized device reached a maximum of 7.17%, which is significant when using a toxicant-free layer. The open-circuit voltage was improved to 0.80 V from 0.47 V in comparison to a reference a-Si:H TFSC without PFN, and the stability in light and dark conditions were greatly enhanced. The fill factor was increased from 0.45 to 0.59 because of the enhancement in shunt/series resistance. The improvement in device performance is mainly due to the creation of an interfacial dipole by the PFN layer, which generated the Vbi across the p-type Si layer, decreased the potential barrier between the i-Si layer and aluminum cathode, and consequently reduced the defects resulting from the coating of the i-Si layer and enhanced electron extraction.
KW - A-Si:H thin-film solar cells
KW - PFN interfacial dipole layer
KW - n-type dopant-free solar cells
UR - http://www.scopus.com/inward/record.url?scp=85018477052&partnerID=8YFLogxK
U2 - 10.1016/j.synthmet.2017.04.014
DO - 10.1016/j.synthmet.2017.04.014
M3 - Article
AN - SCOPUS:85018477052
SN - 0379-6779
VL - 228
SP - 91
EP - 98
JO - Synthetic Metals
JF - Synthetic Metals
ER -