The Mechanism of Hot Spots Caused by Avalanche Breakdown in Gallium-Doped PERC Solar Cells
Author:
Ge Huayun12,
Li Xing1,
Guo Chunlin12,
Luo Wei12,
Jia Rui12
Affiliation:
1. Institute of Microelectronics of the Chinese Academy of Sciences, Beijing 100029, China
2. University of Chinese Academy of Sciences, Beijing 101408, China
Abstract
Gallium-doped p-type passivated emitter and rear contact (PERC) solar cells, which eliminate light-induced degradation (LID) and reduce the impact of light- and elevated-temperature-induced degradation (LeTID), have completely replaced boron-doped p-type PERC cells. However, in previous experiments, we found hot spots in the center of gallium-doped PERC solar cells. In this study, it was found that gallium-doped PERC cells had uneven resistivity, which caused hot spots brought about by the avalanche breakdown of PN junctions. There were significant hot spots in the center of the tested cells, with an average resistivity of 0.4–0.5 Ωcm and nonuniformity greater than 30%, or at an average resistivity of 0.5–0.6 Ωcm with nonuniformity greater than 40%. In this paper we describe and study in detail hot spots triggered by the uneven resistivity of gallium-doped cells and analyze the causes and related influencing factors, thereby providing guidance and a reference for the improvement of the performance and reliability of gallium-doped PERC solar cells.
Funder
National Key Research and Development Program of China
National Natural Science Foundation of China
Natural Science Foundation of Beijing Municipality
Subject
Energy (miscellaneous),Energy Engineering and Power Technology,Renewable Energy, Sustainability and the Environment,Electrical and Electronic Engineering,Control and Optimization,Engineering (miscellaneous),Building and Construction
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