Sulfur-Enhanced Field-Effect Passivation using (NH4)2S Surface Treatment for Black Si Solar Cells

Dae Woong Kim; Jae-Won Song; Hyun Soo Jin; Bongyoung Yoo; Jung-Ho Lee; Tae Joo Park

doi:10.1021/acsami.9b05589

Sulfur-Enhanced Field-Effect Passivation using (NH₄)₂S Surface Treatment for Black Si Solar Cells

ACS Appl Mater Interfaces. 2019 Jul 17;11(28):25140-25146. doi: 10.1021/acsami.9b05589. Epub 2019 Jul 1.

Authors

Dae Woong Kim¹, Jae-Won Song¹, Hyun Soo Jin¹, Bongyoung Yoo¹, Jung-Ho Lee¹, Tae Joo Park¹

Affiliation

¹ Department of Materials Science and Chemical Engineering , Hanyang University , Ansan 15588 , Korea.

PMID: 31259511
DOI: 10.1021/acsami.9b05589

Abstract

We demonstrated surface passivation of a black Si-based solar cell using an (NH₄)₂S solution to mitigate surface recombination velocity. Incorporated S at the interface between atomic-layer-deposited Al₂O₃ and black Si by (NH₄)₂S solution treatment boosted the density of negative fixed charges, S-enhanced field-effect passivation. Furthermore, NH₄OH generated during (NH₄)₂S solution treatment removed the defective Si phase at the black Si surface, the surface cleaning effect. The optimized (NH₄)₂S solution treatment significantly enhanced the internal quantum efficiency up to ∼17.2% in the short wavelength region, suggesting suppressed surface recombination. As a result, photoconversion efficiency of the cell increased from 11.6 to 13.5%, by 16% compared to the control cells without (NH₄)₂S solution treatment.

Keywords: (NH)S; S passivation; Si photovoltaics; black Si; field-effect passivation.