Regensburg 2019 – wissenschaftliches Programm
HL 34.6: Vortrag
Mittwoch, 3. April 2019, 16:30–16:45, H36
Numerical and experimental analysis of the time resolved photo-luminescence method at the buffer-absorber interface of CIGS thin film solar cell — •Ashwin Hariharan, Ievgeniia Savchenko, Jörg Ohland, Hippolyte Hirwa, and Stephan Heise — LCP, University of Oldenburg, Oldenburg, Germany
The minority carrier lifetime is an important second level parameter which affects the primary parameters of the solar cell. To study the minority carrier lifetime - or more generally, the carrier dynamics -, time-resolved photoluminescence (TRPL) method is a powerful technique. The main result obtained from TRPL is the luminescence decay time (or in some cases more than one decay constant), after which two questions follow: (i) under which circumstances is the decay time a direct indicator of minority carrier lifetime, and (ii) is the correlation between minority carrier lifetime and open-circuit voltage valid across all cases. The primary objective of this research is to understand the first correlation in a more perfect manner by studying the charge carrier separation near the heterojunction of CdS/CIGSe. The study includes both experimental analysis and simulation using, Synopsys TCAD. Experimentally, the main analysis involves wavelength-dependent pulsed illumination through which one gains control of the carrier injection density at different depths inside the absorber layer. For simulation, accurate representation of material parameters in the space charge region of the junction will be done. Based on the baseline model, dependence between physical parameters must be found in order to establish the agreement between numerical and experimental decay curves.