原子层沉积工艺对TOPCon太阳电池电性能的影响研究OA

This paper studies the effect of Al2O3 thin film prepared by ALD process on the electrical performance of TOPCon solar cells.The research results show that:1)The hidden open circuit voltage of TOPCon solar cells obtained when the Al2O3 thin film thickness is 9 nm prepared by spatial deposition method is the same as that obtained when the Al2O3 thin film thickness is 5 nm prepared by time-based deposition method.And when the passivation effect of Al2O3 thin films obtained by the two deposition methods are equivalent,there is no significant difference in the electrical performance of TOPCon solar cells prepared.2)When using a time-based deposition method,the TOPCon solar cell obtained with 32 cycles has the highest photoelectric conversion efficiency.3)Compared to TOPCon solar cells without ozone pretreatment,the photoelectric conversion efficiency of TOPCon solar cells did not improve after adding ozone pretreatment.The possible reasons for this result may be:① There is a hydrogen peroxide cleaning process before the deposition of Al2O3 thin film in the TOPCon solar cells without ozone pretreatment,which plays an oxidizing role,a SiO2 layer has been formed between the silicon and Al2O3 thin film interface,which has excellent surface passivation effect.② The gas supply method of the time-based tubular ALD equipment results in different stability of ozone at different positions in the reactor cavity,especially at the tail position where the silicon wafer has lower adsorption of ozone.4)The time-based deposition method has the problem of a large coating area affecting the appearance of the silicon wafer backside.Althongh the spatial deposition method can effectively solve the coating problem,its drawbacks lie in the large footprint of the equipment,low production capacity per unit area,and long maintenance time,which is not conducive to cost reduction in large-scale production.