Berlin 2012 – wissenschaftliches Programm
Bereiche | Tage | Auswahl | Suche | Aktualisierungen | Downloads | Hilfe
HL: Fachverband Halbleiterphysik
HL 38: Photovoltaics: CIGS and related Materials
HL 38.7: Vortrag
Dienstag, 27. März 2012, 12:45–13:00, ER 270
Investigations of lateral and vertical compositional gradients in Cu(In,Ga)Se2 prepared through Rapid Thermal Processing by highly spatially and spectrally resolved cathodoluminescence spectroscopy — •Mathias Müller1, Stefan Ribbe1, Frank Bertram1, Thomas Hempel1, Humberto Rodriguez-Alvarez2, Jakob Lauche2, Hans-Werner Schock2, and Jürgen Christen1 — 1Institute for Experimental Physics, Otto-vonGuericke-University Magdeburg, Germany — 2Helmholtz Center Berlin for Materials and Energy, Germany
We analyze Cu(In,Ga)Se2 thin films using highly spatially and spectrally resolved cathodoluminescence (CL) spectroscopy at low temperature (T = 5 K). The films were deposited by means of a rapid thermal selenization process with growth times varying from 70 to 150 seconds. We find that lateral integral spectra exhibit a broad dominant peak with energies from 0.95 eV to 0.99 eV and a shoulder on the low-energy side. By varying the excitation density, a shift to higher energies of the main peak by 12.8 meV/decade can be observed for the samples with growth times of 100 s and 120 s. Investigations of the cross-sections reveal two distinct regions in the layer sequence. A Ga-rich layer next to the back contact can be identified showing lower luminescence intensities. In contrast, the layer on top reveals an In-rich concentration.