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DTSTART:19700329T020000
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UID:ude20171129100000
CLASS:PUBLIC
SUMMARY:Cu In,Ga Se2 at the micro- and nanometer scale
DTSTART;TZID=Europe/Berlin:20171129T100000
DTEND;TZID=Europe/Berlin:20171129T000000
DTSTAMP:20171129T100000Z
LOCATION;ENCODING=QUOTED-PRINTABLE:Campus Campus Duisburg : BA 115
CONTACT:Dr. Tobias Teckentrup ()
DESCRIPTION:Dr. Tobias Teckentrup ()
Cu In,Ga Se2 at the micro- and nanometer scale
Dr. Sascha Sadewasser - Laboratory for Nanostructured Solar Cells INL
Polycrystalline p-type Cu(In,Ga)Se2 (CIGSe) semiconductors represent the absorber material in the thin film solar cells which currently reach the highest power conversion efficiency. The recent efficiency improvements have been achieved by the introduction of a potassium fluoride post-deposition treatment (KF-PDT). Direct and indirect effects of potassium at the interface and interface-near region in the CIGSe layer are thought to be responsible for this improvement. Using Kelvin probe force microscopy (KPFM), we show that also the electronic properties of grain boundaries (GBs) are beneficially modified by the KF-PDT. KPFM images spatially resolved surface potential of the CIGS surface. We observe that the KF-PDT increases the band bending at GBs by about 70% and results in a narrower distribution of work function values at the GBs [1]. 

[1] N. Nicoara, Th. Lepetit, L. Arzel, S. Harel, N. Barreau, and S. Sadewasser, Scientific Reports 7, 41361 (2017).
Wednesday, 29. November 2017
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