Thermal Annealing Affects Vertical Morphology, Doping and Defect Density in BHJ OPV Devices

Alexandre M. Nardes; Craig L. Perkins; Peter Graf; Jian V. Li; Sean E. Shaheen; David Ostrowski; Andrew Watte; Dana C. Olson; Nikos Kopidakis

doi:10.1109/PVSC.2014.6925457

Thermal Annealing Affects Vertical Morphology, Doping and Defect Density in BHJ OPV Devices

Alexandre M. Nardes, Craig L. Perkins, Peter Graf, Jian V. Li, Sean E. Shaheen, David Ostrowski, Andrew Watte, Dana C. Olson, Nikos Kopidakis

Research output: Contribution to conference › Paper › peer-review

1 Scopus Citations

Abstract

We demonstrate that a post-annealing step results in enhanced open-circuit voltage (V_oc) and fill factor (FF) and lower reverse saturation current (J_s) that consequently increases the power conversion efficiency (PCE) of organic bulk-heterojunction (BHJ) devices by about 40 % as a result of better contact formation, as typically assumed. Although true, we show that additional device properties are affected as well. We found that annealing induces vertical phase segregation and consequently the enrichment of donor and acceptor materials at the correct electrical contact. In addition, a de-doping process and a decrease in defect density also take place and are the major causes for device improvement after post-annealing the OPV devices. Implications for OPV basic research and manufacturing are discussed.

Original language	American English
Pages	2575-2580
Number of pages	6
DOIs	https://doi.org/10.1109/PVSC.2014.6925457 https://doi.org/10.1109/PVSC.2014.6925457
State	Published - 15 Oct 2014
Event	40th IEEE Photovoltaic Specialist Conference, PVSC 2014 - Denver, United States Duration: 8 Jun 2014 → 13 Jun 2014

Conference

Conference	40th IEEE Photovoltaic Specialist Conference, PVSC 2014
Country/Territory	United States
City	Denver
Period	8/06/14 → 13/06/14

Bibliographical note

Publisher Copyright:
© 2014 IEEE.

NREL Publication Number

NREL/CP-5900-62179

Keywords

capacitance
defects
organic semiconductors
photovoltaic cells

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This output contributes to the following UN Sustainable Development Goals (SDGs)

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Nardes, A. M., Perkins, C. L., Graf, P., Li, J. V., Shaheen, S. E., Ostrowski, D., Watte, A., Olson, D. C., & Kopidakis, N. (2014). Thermal Annealing Affects Vertical Morphology, Doping and Defect Density in BHJ OPV Devices. 2575-2580. Paper presented at 40th IEEE Photovoltaic Specialist Conference, PVSC 2014, Denver, United States. https://doi.org/10.1109/PVSC.2014.6925457, https://doi.org/10.1109/PVSC.2014.6925457

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title = "Thermal Annealing Affects Vertical Morphology, Doping and Defect Density in BHJ OPV Devices",

abstract = "We demonstrate that a post-annealing step results in enhanced open-circuit voltage (Voc) and fill factor (FF) and lower reverse saturation current (Js) that consequently increases the power conversion efficiency (PCE) of organic bulk-heterojunction (BHJ) devices by about 40 % as a result of better contact formation, as typically assumed. Although true, we show that additional device properties are affected as well. We found that annealing induces vertical phase segregation and consequently the enrichment of donor and acceptor materials at the correct electrical contact. In addition, a de-doping process and a decrease in defect density also take place and are the major causes for device improvement after post-annealing the OPV devices. Implications for OPV basic research and manufacturing are discussed.",

keywords = "capacitance, defects, organic semiconductors, photovoltaic cells",

author = "Nardes, {Alexandre M.} and Perkins, {Craig L.} and Peter Graf and Li, {Jian V.} and Shaheen, {Sean E.} and David Ostrowski and Andrew Watte and Olson, {Dana C.} and Nikos Kopidakis",

note = "Publisher Copyright: {\textcopyright} 2014 IEEE.; 40th IEEE Photovoltaic Specialist Conference, PVSC 2014 ; Conference date: 08-06-2014 Through 13-06-2014",

year = "2014",

month = oct,

day = "15",

doi = "10.1109/PVSC.2014.6925457",

language = "American English",

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Nardes, AM, Perkins, CL , Graf, P, Li, JV, Shaheen, SE, Ostrowski, D, Watte, A, Olson, DC & Kopidakis, N 2014, 'Thermal Annealing Affects Vertical Morphology, Doping and Defect Density in BHJ OPV Devices', Paper presented at 40th IEEE Photovoltaic Specialist Conference, PVSC 2014, Denver, United States, 8/06/14 - 13/06/14 pp. 2575-2580. https://doi.org/10.1109/PVSC.2014.6925457, https://doi.org/10.1109/PVSC.2014.6925457

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T1 - Thermal Annealing Affects Vertical Morphology, Doping and Defect Density in BHJ OPV Devices

AU - Nardes, Alexandre M.

AU - Perkins, Craig L.

AU - Graf, Peter

AU - Li, Jian V.

AU - Shaheen, Sean E.

AU - Ostrowski, David

AU - Watte, Andrew

AU - Olson, Dana C.

AU - Kopidakis, Nikos

PY - 2014/10/15

Y1 - 2014/10/15

N2 - We demonstrate that a post-annealing step results in enhanced open-circuit voltage (Voc) and fill factor (FF) and lower reverse saturation current (Js) that consequently increases the power conversion efficiency (PCE) of organic bulk-heterojunction (BHJ) devices by about 40 % as a result of better contact formation, as typically assumed. Although true, we show that additional device properties are affected as well. We found that annealing induces vertical phase segregation and consequently the enrichment of donor and acceptor materials at the correct electrical contact. In addition, a de-doping process and a decrease in defect density also take place and are the major causes for device improvement after post-annealing the OPV devices. Implications for OPV basic research and manufacturing are discussed.

AB - We demonstrate that a post-annealing step results in enhanced open-circuit voltage (Voc) and fill factor (FF) and lower reverse saturation current (Js) that consequently increases the power conversion efficiency (PCE) of organic bulk-heterojunction (BHJ) devices by about 40 % as a result of better contact formation, as typically assumed. Although true, we show that additional device properties are affected as well. We found that annealing induces vertical phase segregation and consequently the enrichment of donor and acceptor materials at the correct electrical contact. In addition, a de-doping process and a decrease in defect density also take place and are the major causes for device improvement after post-annealing the OPV devices. Implications for OPV basic research and manufacturing are discussed.

KW - capacitance

KW - defects

KW - organic semiconductors

KW - photovoltaic cells

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DO - 10.1109/PVSC.2014.6925457

M3 - Paper

AN - SCOPUS:84912141973

SP - 2575

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T2 - 40th IEEE Photovoltaic Specialist Conference, PVSC 2014

Y2 - 8 June 2014 through 13 June 2014

ER -

Thermal Annealing Affects Vertical Morphology, Doping and Defect Density in BHJ OPV Devices

Abstract

Conference

Bibliographical note

NREL Publication Number

Keywords

UN SDGs

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