Berlin 2008 – wissenschaftliches Programm

Bereiche | Tage | Auswahl | Suche | Downloads | Hilfe

HL: Fachverband Halbleiterphysik

HL 17: Poster I

HL 17.25: Poster

Montag, 25. Februar 2008, 16:30–19:00, Poster D

Composition Dependence of Defects in CuIn1-xGaxSe2 Solar Cells — •Tobias Eisenbarth, Thomas Unold, Christian Kaufmann, Raquel Caballero, Daniel Abou-Ras, and Hans-Werner Schock — Hahn-Meitner-Institut, Glienicker Str. 100, 14109 Berlin, Germany

Chalcopyrite solar cells based on CuIn1-xGaxSe2 absorber layers so far yield the highest thin film solar cell efficiencies, with the potential to surpass the 20% efficiency mark in the near future. There are still a number of fundamental questions about the relation between the composition and the structural and electronic properties of the absorber films, in particular the relationship between the structural and electronic defects and their effect on the device performance of the solar cells. To investigate this issue further a series of CuIn1-xGaxSe2 solar cells was prepared with 0 < x < 1, covering the full range of gallium/indium ratios using our standard three-stage co-evaporation process. The cross-section of the solar cells has been investigated in a SEM system to reveal details about the structure. On the same cells, defect spectroscopy was performed using admittance spectroscopy and drive-level capacitance profiling, to obtain an estimate of the number of deep defects present in the devices. Additionally, photoluminescence spectroscopy was applied to obtain more information about the recombination properties of the series of devices.