On the Kinetics of Light‐Induced Enhancement Effect in Silicon Heterojunction Solar Cells

Abstract

Silicon heterojunction (SHJ) solar cells are one of the promising technologies for next‐generation high‐efficiency crystalline silicon solar cells in photovoltaic industry. Recently, an interesting light‐induced performance enhancement (LIE) effect has been observed in SHJ solar cells. Herein, the kinetics and stability of the LIE effect during repeated cycles of light soaking and subsequent dark annealing at 150 °C are investigated. It is found that VOC of SHJ solar cells increases with light soaking time following stretched exponential, but can be reverted by subsequent dark annealing. This means that LIE effect in SHJ solar cells is not stable. The underlying mechanism of this phenomenon should be attributed to the hydrogen motion in a‐Si:H layers. It is also demonstrated that increasing illumination intensity leads to faster (shorter time constant) and stronger (higher saturation level of ΔVOC) LIE effect.