Open AccessOne‐Step Formation of Low Work‐Function, Transparent and Conductive MgF x O y Electron Extraction for Silicon Solar Cells
Author(s) -
Li Junjun,
Guo Cong,
Bai Yu,
Liu Wenzhu,
Chen Yang,
He Jialong,
Li Dongdong,
Yang Xinbo,
Qiu Qingqing,
Chen Tao,
Yu Junsheng,
Huang Yuelong,
Yu Jian
Publication year - 2022
Publication title -
advanced science
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 5.388
H-Index - 100
ISSN - 2198-3844
DOI - 10.1002/advs.202202400
Subject(s) - dopant , materials science , work function , solar cell , doping , indium tin oxide , silicon , optoelectronics , indium , nanotechnology , transparent conducting film , thin film , layer (electronics)
The development of high‐performance dopant‐free silicon solar cells is severely bottlenecked by opaque electron selective contact. In this paper, high transmittance (80.5% on glass) and low work function (2.92 eV) lithium fluoride (LiF x )/MgF x O y electron contact stack by tailoring the composition of MgF x O y hybrid film is reported. This hybrid structure exhibits a high conductivity (2978.4 S cm −1 ) and a low contact resistivity (2.0 mΩ cm 2 ). The element profile of LiF x /MgF x O y contact is measured and the reaction kinetics is analyzed. As a proof‐of‐concept, this electron selective contact is applied for dopant‐free silicon solar cells. An impressive efficiency of 21.3% is achieved on dopant‐free monofacial solar cell with molybdenum oxide (MoO x )/zinc‐doped indium oxide (IZO) hole contact. An efficiency bifaciality of 71% is obtained for dopant‐free bifacial solar cell with full‐area LiF x /MgF x O y /ITO (tin‐doped indium oxide) transparent electron contact. It is the highest efficiency bifaciality so far for dopant‐free bifacial solar cells to the best knowledge. Both cell configurations with LiF x /MgF x O y contacts show excellent environment stability. The cell efficiency maintains more than 95% of its initial value after keeping in air for 1500 h. This work provides a new idea to achieve transparent electron contact, showing a great potential for high‐efficiency and low‐cost optoelectronic devices.