Back interface passivation reduces the back recombination of photogenerated electrons, whereas aggravates the blocking of hole transport towards back contact, which complicate the back interface engineering for ultrat...Back interface passivation reduces the back recombination of photogenerated electrons, whereas aggravates the blocking of hole transport towards back contact, which complicate the back interface engineering for ultrathin CIGSe solar cells with a Schottky back contact. In this work, theoretical explorations were conducted to study how the two contradictory electrical effects impact cell performance. For ultrathin CIGSe solar cells with a pronounced Schottky potential barrier(E_(h)> 0.2 eV), back interface passivation produces diverse performance evolution trends, which are highly dependent on cell structures and properties. Since a back Ga grading can screen the effect of reduced recombination of photogenerated electrons from back interface passivation, the hole blocking effect predominates and back interface passivation is not desirable. However, when the back Schottky diode merges with the main pn junction due to a reduced absorber thickness,the back potential barrier and the hole blocking effect is much reduced on this occasion. Consequently, cells exhibit the same efficiency evolution trend as ones with an Ohmic contact, where back interface passivation is always advantageous.The discoveries imply the complexity of back interface passivation and provide guidance to manipulate back interface for ultrathin CIGSe solar on TCOs with a pronounced Schottky back contact.展开更多
采用PC1D软件仿真分析钝化发射极及背接触(passivation emitter and rear contact,PERC)电池;模拟结果表明:降低电池的背表面复合速率有利于增强电池性能、提高电池长波响应。PERC电池由于背表面钝化可采用较低的背场厚度;背钝化层...采用PC1D软件仿真分析钝化发射极及背接触(passivation emitter and rear contact,PERC)电池;模拟结果表明:降低电池的背表面复合速率有利于增强电池性能、提高电池长波响应。PERC电池由于背表面钝化可采用较低的背场厚度;背钝化层中的表面电荷对高背表面复合速率的电池性能的提升作用显著,但在背表面复合速率较低时影响不大;实测得到PERC电池比常规全铝背接触电池的开路电压和短路电流分别增大1.56%和2.56%。展开更多
基金Project supported by the National Natural Science Foundation of China (Grant No. 51802240)。
文摘Back interface passivation reduces the back recombination of photogenerated electrons, whereas aggravates the blocking of hole transport towards back contact, which complicate the back interface engineering for ultrathin CIGSe solar cells with a Schottky back contact. In this work, theoretical explorations were conducted to study how the two contradictory electrical effects impact cell performance. For ultrathin CIGSe solar cells with a pronounced Schottky potential barrier(E_(h)> 0.2 eV), back interface passivation produces diverse performance evolution trends, which are highly dependent on cell structures and properties. Since a back Ga grading can screen the effect of reduced recombination of photogenerated electrons from back interface passivation, the hole blocking effect predominates and back interface passivation is not desirable. However, when the back Schottky diode merges with the main pn junction due to a reduced absorber thickness,the back potential barrier and the hole blocking effect is much reduced on this occasion. Consequently, cells exhibit the same efficiency evolution trend as ones with an Ohmic contact, where back interface passivation is always advantageous.The discoveries imply the complexity of back interface passivation and provide guidance to manipulate back interface for ultrathin CIGSe solar on TCOs with a pronounced Schottky back contact.
文摘采用PC1D软件仿真分析钝化发射极及背接触(passivation emitter and rear contact,PERC)电池;模拟结果表明:降低电池的背表面复合速率有利于增强电池性能、提高电池长波响应。PERC电池由于背表面钝化可采用较低的背场厚度;背钝化层中的表面电荷对高背表面复合速率的电池性能的提升作用显著,但在背表面复合速率较低时影响不大;实测得到PERC电池比常规全铝背接触电池的开路电压和短路电流分别增大1.56%和2.56%。