Dresden 2009 – scientific programme
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HL: Fachverband Halbleiterphysik
HL 18: Impurities/amorphous semiconductors
HL 18.1: Talk
Tuesday, March 24, 2009, 12:00–12:15, POT 151
Pulsed electrically detected magnetic resonance study of spin relaxation and recombination in thin-film silicon solar cells — •Matthias Fehr1, Jan Behrends1, Alexander Schnegg1, Klaus Lips1, Bernd Rech1, Oleksandr Astakhov2, and Friedhelm Finger2 — 1Helmholtz-Zentrum Berlin, Silizium Photovoltaik, 12489 Berlin, Germany — 2Forschungszentrum Jülich, IEF-5 Photovoltaik, 52425 Jülich, Germany
We have investigated the influence of paramagnetic states on electronic transport processes in thin-film pin solar cells with pulsed Electrically Detected Magnetic Resonance (pEDMR) at X-Band frequency and low temperature (10 K). The solar cells consist of an intrinsic microcrystalline absorber layer and amorphous or microcrystalline n/p contacting layers. In addition to the identification of the participating paramagnetic centres by their g-factors, pEDMR can be used to study the dynamics of the electronic processes in detail. We present measurements of modified EPR pulse sequences in order to identify the dominating relaxation mechanisms within correlated solid-state spin-pairs. By this technique a monitoring of the spin and charge motion is possible. In the outlook we present measurements of the electron spin echo envelope and critically discuss modulations in terms of dipolar coupling within the spin-pairs or hyperfine couplings to surrounding nuclei.