p-Type <formula formulatype="inline"><tex Notation="TeX">CuₓO</tex> </formula> Thin-Film Transistors Produced by Thermal Oxidation

Thin-films of copper oxide(CuₓO)were produced by thermal oxidation of metallic copper (Cu) at different temperatures (150–450\ ∘C). The films produced at temperatures of 200, 250 and 300\ ∘Cshowed high Hall motilities of 2.2, 1.9 and 1.6cm²\ V⁻¹s⁻¹, respectively. SingleCu₂Ophases were obtained at 200\ ∘Cand its conversion to CuO starts at 250\ ∘C. For lower thicknesses~40 nm, the films oxidized at 250\ ∘Cshowed a complete conversion to CuO phase. Successful thin-film transistors (TFTs) were produce by thermal oxidation of a 20 nm Cu film, obtaining p-typeCu₂O(at 200\ ∘C) and CuO (at 250\ ∘C) with On/Off ratios of6× 10¹and1× 10², respectively.