TY - JOUR
T1 - Fundamental understanding, impact, and removal of boron-rich layer on n-type silicon solar cells
AU - Ryu, Kyungsun
AU - Choi, Chel Jong
AU - Park, Hyomin
AU - Kim, Donghwan
AU - Rohatgi, Ajeet
AU - Ok, Young Woo
N1 - Funding Information:
This research was supported by Basic Science Research Program ( NRF-2015R1A6A1A04020421 ) through the National Research Foundation of Korea (NRF) funded by the Ministry of Education, Republic of Korea, and by the Converging Research Center Program ( 2014M3C1A8048834 ) through the Ministry of Science, ICT & Future Planning, Republic of Korea .
PY - 2016/3/1
Y1 - 2016/3/1
N2 - Most boron diffusion technologies result in the formation of an undesirable boron-rich layer (BRL) on the emitter surface. This paper reports on a study of the impact of gradual etching of the BRL on n-type silicon solar cell performance. It is found that gradual removal of the BRL improves surface passivation and bulk lifetime in the finished cell, while over-etching of the BRL results in a sharp decrease in fill factor due to the increased n-factor and series resistance. It is shown that the optimum chemical etching of the BRL formed as a byproduct of the screen-printed boron emitter diffusion used in this study raised the cell efficiency by -0.5%, resulting in 20.0% efficient large area (239 cm2) n-type solar cells. The change in BRL thickness and morphology as a function of chemical etching time was investigated by TEM and AES measurements to explain the quantitative impact of BRL removal on cell performance.
AB - Most boron diffusion technologies result in the formation of an undesirable boron-rich layer (BRL) on the emitter surface. This paper reports on a study of the impact of gradual etching of the BRL on n-type silicon solar cell performance. It is found that gradual removal of the BRL improves surface passivation and bulk lifetime in the finished cell, while over-etching of the BRL results in a sharp decrease in fill factor due to the increased n-factor and series resistance. It is shown that the optimum chemical etching of the BRL formed as a byproduct of the screen-printed boron emitter diffusion used in this study raised the cell efficiency by -0.5%, resulting in 20.0% efficient large area (239 cm2) n-type solar cells. The change in BRL thickness and morphology as a function of chemical etching time was investigated by TEM and AES measurements to explain the quantitative impact of BRL removal on cell performance.
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U2 - 10.1016/j.solmat.2015.11.031
DO - 10.1016/j.solmat.2015.11.031
M3 - Article
AN - SCOPUS:84949008523
VL - 146
SP - 58
EP - 62
JO - Solar Energy Materials and Solar Cells
JF - Solar Energy Materials and Solar Cells
SN - 0927-0248
ER -