Scalable deposition of SnO2 ETL via SALD for large-area inverted perovskite solar modules

Abstract

Tin dioxide (SnO₂) stands out as a promising candidate for the electron transport layer (ETL) in perovskite solar cells (PSCs) due to its remarkable conductivity. As PSCs progress towards commercialization, the scalability of deposition methods, cost-effectiveness, and the seamless integration of various material layers become increasingly crucial, alongside the fundamental efficiency requirements. In this study, we demonstrate large-scale deposition of SnO₂ film with low thickness non-uniformity of 2.36 % via Spatial Atomic Layer Deposition (SALD), offering a significant advantage by enabling high-throughput production of large-area films at atmospheric pressure. By exploiting the varying reactivity of oxygen precursors and modulating the flow to control oxygen vacancy defects, SnO₂ film, deposited at 100 °C with Tetrakis(dimethylamino)tin (TDMASn) and H₂O₂, achieved a high mobility of 19.4 cm² V⁻¹ s⁻¹. The 400 cm² perovskite solar modules (PSMs) with optimized SnO₂ ETL achieved a high power conversion efficiency (PCE) of 19.35 %, marking a notably high PCE of inverted PSCs with such a large area to date. This exceptional performance stems from the excellent uniformity and mobility of the SALD-deposited SnO₂ ETL, highlighting the potential of SALD in future PSM fabrication.