An industrial solution to light-induced degradation of crystalline silicon solar cells

Abstract

Boron-oxygen defects can cause serious light-induced degradation (LID) of commercial solar cells based on the boron-doped crystalline silicon (c-Si), which are formed under the injection of excess carriers induced either by illumination or applying forward bias. In this contribution, we have demonstrated that the passivation process of boron-oxygen defects can be induced by applying forward bias for a large quantity of solar cells, which is much more economic than light illumination. We have used this strategy to trigger the passivation process of batches of aluminum back surface field (Al-BSF) solar cells and passivated emitter and rear contact (PERC) solar cells. Both kinds of the treated solar cells show high stability in efficiency and suffer from very little LID under further illumination at room temperature. This technology is of significance for the suppression of LID of c-Si solar cells for the industrial manufacture.

Key words： Boron-oxygen defects; c-Si solar cells; light-induced degradation; passivation; forward bias

Acknowledgments

This work was supported by the National Natural Science Foundation of China (Grant Nos. 51532007, 61574124 and 51472219), the Program for Innovative Research Team in University of Ministry of Education of China (IRT13R54), and State Key Laboratory of Optoelectronic Materials and Technologies (Sun Yat-sen University).

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