18.4%-Efficient Heterojunction Si Solar Cells Using Optimized ITO/Top Electrode.
We optimize the thickness of a transparent conducting oxide (TCO) layer, and apply a microscale mesh-pattern metal electrode for high-efficiency a-Si/c-Si heterojunction solar cells. A solar cell equipped with the proposed microgrid metal electrode demonstrates a high short-circuit current density (JSC) of 40.1 mA/cm(2), and achieves a high efficiency of 18.4% with an open-circuit voltage (VOC) of 618 mV and a fill factor (FF) of 74.1% as result of the shortened carrier path length and the decreased electrode area of the microgrid metal electrode. Furthermore, by optimizing the process sequence for electrode formation, we are able to effectively restore the reduction in VOC that occurs during the microgrid metal electrode formation process. This work is expected to become a fundamental study that can effectively improve current loss in a-Si/c-Si heterojunction solar cells through the optimization of transparent and metal electrodes.
Department of Energy Engineering, UNIST , Ulsan 44919, Republic of Korea.
Namwoo
N
Kim
Department of Energy Engineering, UNIST , Ulsan 44919, Republic of Korea.
Han-Don
HD
Um
KIER-UNIST, Advanced Center for Energy, Korea Institute for Energy Research , Ulsan 44919, Republic of Korea.
Inwoo
I
Choi
KIER-UNIST, Advanced Center for Energy, Korea Institute for Energy Research , Ulsan 44919, Republic of Korea.
Ka-Hyun
KH
Kim
Department of Energy Engineering, UNIST , Ulsan 44919, Republic of Korea.
Kwanyong
K
Seo
D004566:Electrodes; D008670:Metals; D010087:Oxides; D012825:Silicon / Q000737:chemistry*; D012993:Solar Energy; D013472:Sunlight
D008670:Metals; D010087:Oxides; D012825:Silicon
current loss; heterojunction solar cell; indium tin oxide; microgrid; top electrode