| Title |
Positron Annihilation Studies on the Damp Heat Degradation of ZnO:Al Transparent Conductive Oxide Layers for CIGS Solar Cells |
| ID_Doc |
65038 |
| Authors |
Shi, WQ; Theelen, M; Gevaerts, V; Illiberi, A; Barreau, N; Butterling, M; Schut, H; Egger, W; Dickmann, M; Hugenschmidt, C; Zeman, M; Brück, E; Eijt, SWH |
| Title |
Positron Annihilation Studies on the Damp Heat Degradation of ZnO:Al Transparent Conductive Oxide Layers for CIGS Solar Cells |
| Year |
2018 |
| Published |
Ieee Journal Of Photovoltaics, 8.0, 6 |
| DOI |
10.1109/JPHOTOV.2018.2863788 |
| Abstract |
Positron annihilation depth-profiling is used as an innovative tool to monitor the evolution of vacancy defects in two series of ZnO:Al transparent conductive oxide (TCO) layers for Cu(In,Ga)Se-2 (CIGS) solar cells under accelerated degradation at 85 degrees C/85% relative humidity. The first series of ZnO:Al layers are deposited directly on flat glass substrates, leading to low densities of (extended) grain boundaries in the ZnO:Al. These ZnO:Al layers only show an increase in open volume upon degradation in the near-surface range. The second series of ZnO:Al layers are deposited on the more corrugated surface of CdS/CIGS/Mo solar cells, and show, on the other hand, a pronounced formation of open volume throughout the layer. Its depth-dependence is consistent with in-diffusion of molecules such as H2O and CO2 into the ZnO:Al layer via the grain boundaries, as primary driver for the degradation. The detected time-dependence of the growth of open volume at the grain boundaries in the ZnO:Al TCO layer matches the time scale of the observed reduction in solar cell efficiency and series resistance, suggesting that the generated open volume induces a significant barrier against charge carrier transport. |
| Author Keywords |
Buffer layers; and back contacts; CIGS and CdTe thin film solar cells; degradation; grain boundaries; positrons; transparent conductors; ZnO:Al |
| Index Keywords |
Index Keywords |
| Document Type |
Other |
| Open Access |
Open Access |
| Source |
Science Citation Index Expanded (SCI-EXPANDED) |
| EID |
WOS:000448898400060 |
| WoS Category |
Energy & Fuels; Materials Science, Multidisciplinary; Physics, Applied |
| Research Area |
Energy & Fuels; Materials Science; Physics |
| PDF |
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