[17p-A403-1~17] 16.3 Bulk, thin-film and other silicon-based solar cells

[17p-A403-14] Effect of a LiF layer on passivation performance after Al deposition in TiO_x/SiO_y/crystalline Si heterostructures

〇Shohei Fukaya¹, Kazuhiro Gotoh¹, Takuya Matsui², Hitoshi Sai², Yasushoshi Kurokawa¹, Noritaka Usami¹ (1.Graduate School of Eng., Nagoya Univ., 2.GZR, AIST)

Keywords:photovoltaics, titanium oxide

Toward the realization of high-performance, low-cost crystalline silicon (c-Si) heterojunction solar cells, the use of titanium oxide (TiOx) deposited by atomic layer deposition (ALD) as a carrier selective layer has attracted attention. However, the formation of aluminum (Al) electrode on TiOx significantly degrades the passivation performance of c-Si. This may be due to the formation of Al oxide by reduction of titanium oxide at the TiOx/Al interface and diffusion of Al into TiOx and Si, but the details of this problem have not been clarified. In addition, an ultra-thin lithium fluoride (LiF) layer is introduced between TiOx and Al as a method to suppress the degradation of passivation performance, but the research on the passivation mechanism by the LiF layer is not sufficient and further investigation is needed. Therefore, in this study, we investigated the effect of Al deposition on passivation performance by depositing LiF and TiOx in various orders followed by Al electrode formation.