Room-temperature processed high-quality SnO2 films by oxygen plasma activated e-beam evaporation

Abstract

Recently, SnO2 is considered to be one of the most promising materials as electron transport layer in perovskite solar cells (PSCs). Low-temperature processed SnO2 films are crucial for SnO2-based PSCs and flexible devices. However, it is difficult to prepare stoichiometric SnO2 films by e-beam evaporation at low-temperature. Herein, SnO2 films are fabricated by oxygen plasma activated e-beam evaporation technique at room-temperature. Oxygen plasma shows strong oxidation activity, which is essential to adjust the stoichiometry of SnO x in the evaporation process. The SnO2 films exhibit uniformity (R q = 3.05 nm), high transmittance (T > 90%), high hall mobility (μ e = 10.8 cm2 V −1 s−1) and good hydrophilic (water contact angle =19°). This work will promote the application of SnO2 films in PSCs and flexible devices.