Intragrain charge transport in kesterite thin films—Limits arising from carrier localization

doi:10.1063/1.4965868

Title: Intragrain charge transport in kesterite thin films—Limits arising from carrier localization

Abstract

Intragrain charge carrier mobilities measured by time-resolved terahertz spectroscopy in state of the art Cu ₂ZnSn(S,Se) ₄ kesterite thin films are found to increase from 32 to 140 cm ²V ^-1s ^-1 with increasing Se content. The mobilities are limited by carrier localization on the nanometer-scale, which takes place within the first 2 ps after carrier excitation. The localization strength obtained from the Drude-Smith model is found to be independent of the excited photocarrier density. This is in accordance with bandgap fluctuations as a cause of the localized transport. Lastly, charge carrier localization is a general issue in the probed kesterite thin films, which were deposited by coevaporation, colloidal inks, and sputtering followed by annealing with varying Se/S contents and yield 4.9%-10.0% efficiency in the completed device.

Authors:

Hempel, Hannes ^[1]; Redinger, Alex ^[2]; Repins, Ingrid ^[3]; Moisan, Camille ^[4]; Larramona, Gerardo ^[4]; Dennler, Gilles ^[4]; Handwerg, Martin ^[5]; Fischer, Saskia F. ^[5];

^[6]; Unold, Thomas ^[2]

Helmholtz-Zentrum Berlin (HZB), (Germany). German Research Centre for Materials and Energy, Dept. of Structure and Dynamics of Energy Materials
Helmholtz-Zentrum Berlin (HZB), (Germany). German Research Centre for Materials and Energy, Dept. of Structure and Dynamics of Energy Materials
National Renewable Energy Lab. (NREL), Golden, CO (United States)
Inst. Minoru de Recherche Avancee (IMRA), Sophia Antipolis, Cedex (France)
Humboldt Univ. of Berlin (Germany)
Helmholtz-Zentrum Berlin (HZB), (Germany). German Research Centre for Materials and Energy, Inst. for Solar Fuels

Publication Date:: 2016-11-03

Research Org.:: National Renewable Energy Lab. (NREL), Golden, CO (United States)

Sponsoring Org.:: USDOE Office of Energy Efficiency and Renewable Energy (EERE)

OSTI Identifier:: 1334597

Report Number(s):: NREL/JA-5J00-67507
Journal ID: ISSN 0021-8979; JAPIAU

Grant/Contract Number:: AC36-08GO28308

Resource Type:: Accepted Manuscript

Journal Name:: Journal of Applied Physics

Additional Journal Information:: Journal Volume: 120; Journal Issue: 17; Journal ID: ISSN 0021-8979

Publisher:: American Institute of Physics (AIP)

Country of Publication:: United States

Language:: English

Subject:: 14 SOLAR ENERGY; 71 CLASSICAL AND QUANTUM MECHANICS, GENERAL PHYSICS; band gap; grain boundaries; hole mobility; hall mobility; solar cells

Citation Formats


                    Hempel, Hannes, Redinger, Alex, Repins, Ingrid, Moisan, Camille, Larramona, Gerardo, Dennler, Gilles, Handwerg, Martin, Fischer, Saskia F., Eichberger, Rainer, and Unold, Thomas. Intragrain charge transport in kesterite thin films—Limits arising from carrier localization.  United States: N. p., 2016. 
        Web.  doi:10.1063/1.4965868.

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                    Hempel, Hannes, Redinger, Alex, Repins, Ingrid, Moisan, Camille, Larramona, Gerardo, Dennler, Gilles, Handwerg, Martin, Fischer, Saskia F., Eichberger, Rainer, & Unold, Thomas. Intragrain charge transport in kesterite thin films—Limits arising from carrier localization.  United States.  doi:10.1063/1.4965868.

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                    Hempel, Hannes, Redinger, Alex, Repins, Ingrid, Moisan, Camille, Larramona, Gerardo, Dennler, Gilles, Handwerg, Martin, Fischer, Saskia F., Eichberger, Rainer, and Unold, Thomas. Thu .  
        "Intragrain charge transport in kesterite thin films—Limits arising from carrier localization".  United States.  doi:10.1063/1.4965868.  https://www.osti.gov/servlets/purl/1334597.

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@article{osti_1334597,

  title        = {Intragrain charge transport in kesterite thin films—Limits arising from carrier localization},

  author       = {Hempel, Hannes and Redinger, Alex and Repins, Ingrid and Moisan, Camille and Larramona, Gerardo and Dennler, Gilles and Handwerg, Martin and Fischer, Saskia F. and Eichberger, Rainer and Unold, Thomas},

  abstractNote = {Intragrain charge carrier mobilities measured by time-resolved terahertz spectroscopy in state of the art Cu2ZnSn(S,Se)4 kesterite thin films are found to increase from 32 to 140 cm2V-1s-1 with increasing Se content. The mobilities are limited by carrier localization on the nanometer-scale, which takes place within the first 2 ps after carrier excitation. The localization strength obtained from the Drude-Smith model is found to be independent of the excited photocarrier density. This is in accordance with bandgap fluctuations as a cause of the localized transport. Lastly, charge carrier localization is a general issue in the probed kesterite thin films, which were deposited by coevaporation, colloidal inks, and sputtering followed by annealing with varying Se/S contents and yield 4.9%-10.0% efficiency in the completed device.},

  doi          = {10.1063/1.4965868},

  journal      = {Journal of Applied Physics},

  number       = 17,

  volume       = 120,

  place        = {United States},

  year         = {2016},

  month        = {11}

}

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DOI: 10.1063/1.4965868

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Title: Intragrain charge transport in kesterite thin films—Limits arising from carrier localization

Abstract

Citation Formats

A low-temperature order-disorder transition in Cu 2 ZnSnS 4 thin films journal, January 2014

Effects of deposition termination on Cu2ZnSnSe4 device characteristics journal, May 2015

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Luminescence of Cu 2 ZnSnS 4 polycrystals described by the fluctuating potential model journal, June 2013

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Determination of secondary phases in kesterite Cu ₂ ZnSnS ₄ thin films by x-ray absorption near edge structure analysis
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