Implementation and quantification of scanning transmission EBIC experiments for measuring nanometer diffusion lengths in manganite-titanite p-n heterojunctions
von Patrick Peretzki
Datum der mündl. Prüfung:2018-12-19
Erschienen:2019-01-08
Betreuer:Prof. Dr. Michael Seibt
Gutachter:Prof. Dr. Michael Seibt
Gutachter:Prof. Dr. Christian Jooß
Dateien
Name:Peretzki_Diss_Online_optimiert.pdf
Size:11.9Mb
Format:PDF
Description:Dissertation Patrick Peretzki
Zusammenfassung
Englisch
The scanning transmission electron beam induced current (STEBIC) approach to measure charge carrier diffusion lengths in the nanometer range in 3rd generation photovoltaics devices is presented, evaluated and applied to the manganite-titanite p-n heterojunction PCMO-STNO. Quantitative measurement and evaluation of the room temperature diffusion length of PCMO and STNO are enabled by varying electron beam acceleration voltage and sample thickness, using scanning electron microscopy (SEM) as well as transmission electron microscopy (TEM) instrumentation. Low temperature experiments confirm an expected increased PCMO diffusion length. Finally, two promising simulation methods for STEBIC data as well as first studies of the PCMO-STNO heterojunction electric potential by off-axis electron holography are presented and discussed.
Keywords: Electron microscopy; EBIC; Photovoltaics; Nanoscience; Diffusion length; Manganite