The Role of Humidity in Tuning the Texture and Electrical Properties of Cu₂O Thin Films Deposited via Aerosol‐Assisted CVD

Abstract A study on the effect of carrier gas (CG) humidity on the texture and the resulting electronic properties of Cu₂O thin films deposited using aerosol‐assisted chemical vapor deposition (AA‐CVD) at low temperatures (<365 °C) is reported. By increasing the CG humidity, the preferred orientation of the films can be tuned from [110] to [111]. By studying the initial stages of film deposition, a different growth mode is found for dry and humid conditions, which in turn directs the final texture of the films. The analysis of the electric properties of the films by Hall effect shows that carrier concentration remains in the order of 10¹⁵ cm⁻³ when using both dry and humid conditions. Converselly, Cu₂O samples deposited with humid CG generally present a higher mobility, up to 17 cm² V⁻¹ s⁻¹. [111]‐textured Cu₂O films with high mobility were used to fabricate a diode by depositing a ZnO layer on top using atmospheric pressure spatial atomic layer deposition (AP‐SALD). The diode shows an excellent rectifying behavior with a high asymmetry close to 10⁴ between −1 and +1 V.