Dresden 2017 – wissenschaftliches Programm
CPP 20.3: Vortrag
Dienstag, 21. März 2017, 10:15–10:30, ZEU 222
Modulated surface photovoltage spectroscopy of CH3NH3Pb(I,Br)3 thin films — •Celline Awino, Thomas Dittrich, Eva Unger, and Bernd Rech — Helmholtz-Zentrum Berlin für Materialien und Energie GmbH, Institut für Silizium-Photovoltaik, Kekuléstr. 5, 12489 Berlin, Deutschland
The investigation of electronic properties of CH3NH3Pb(I,Br)3 and their dependence on aging and light soaking is important for better understanding of the stability of solar cells based on related materials. Modulated surface photovoltage spectroscopy allows for the ex-situ and in-situ characterization of the band gap, tail states and deep defect states in the band gap, direction of modulated charge separation and diffusion length. It has been found, for example, that the Tauc gap and the energy of exponential tail states sensitively depend on the substrate and on soaking in nitrogen atmosphere and that light soaking has strong influence on the direction and amplitude of modulated charge separation.