TY  - JOUR
AU  - Moulin, Etienne
AU  - Bittkau, Karsten
AU  - Ghosh, Michael
AU  - Bugnon, Grégory
AU  - Stuckelberger, Michael
AU  - Meier, Matthias
AU  - Haug, Franz-Josef
AU  - Hüpkes, Jürgen
AU  - Ballif, Christophe
TI  - Comparison of LPCVD and sputter-etched ZnO layers applied as front electrodes in tandem thin-film silicon solar cells
JO  - Solar energy materials & solar cells
VL  - 145
SN  - 0927-0248
CY  - Amsterdam
PB  - North Holland
M1  - FZJ-2016-00778
SP  - 185 - 192
PY  - 2016
AB  - Aluminum-doped zinc oxide (ZnO:Al) layers deposited by sputtering and boron-doped zinc oxide (ZnO:B) layers deposited by low-pressure chemical vapor deposition (LPCVD) are well-established materials for front electrodes in thin-film silicon solar cells. In this study, both types of front electrodes are evaluated with respect to their inherent properties and their surface textures in micromorph tandem solar cells in the superstrate configuration. The silicon layer stack investigated here consists of a 220-nm-thick amorphous silicon top cell, a 40-nm-thick intermediate reflector and a 1.1-µm-thick microcrystalline silicon bottom cell; for this specific silicon layer stack, the LPCVD ZnO:B provides higher power conversion efficiency than its sputtered ZnO:Al counterpart. The growth-friendly surface topography of ZnO:Al yields better electrical performance. However, tandem cells on ZnO:Al suffer from a fundamental optical limitation in terms of light trapping in the top cell. They also show a higher parasitic absorption linked to the relatively high doping concentration of the ZnO:Al layers used here. Detailed analysis of the experimental results allows us to clearly understand the opto-electrical behavior of both types of cells and envisage several possible upgrades to further improve their performance.
LB  - PUB:(DE-HGF)16
UR  - <Go to ISI:>//WOS:000367772400003
DO  - DOI:10.1016/j.solmat.2015.09.065
UR  - https://juser.fz-juelich.de/record/281073
ER  -