High-Performance Amorphous Multilayered ZnO-SnO2 Heterostructure Thin-Film Transistors: Fabrication and Characteristics.

Multilayered ZnO-SnO₂ heterostructure thin films consisting of ZnO and SnO₂ layers are produced by alternating the pulsed laser ablation of ZnO and SnO₂ targets, and their structural and field-effect electronic transport properties are investigated as a function of the thickness of the ZnO and SnO₂ layers. The performance parameters of amorphous multilayered ZnO-SnO₂ heterostructure thin-film transistors (TFTs) are highly dependent on the thickness of the ZnO and SnO₂ layers. A highest electron mobility of 43 cm²/V∙s, a low subthreshold swing of a 0.22 V/dec, a threshold voltage of 1 V, and a high drain current on-to-off ratio of 10¹⁰ are obtained for the amorphous multilayered ZnO(1.5 nm)-SnO₂(1.5 nm) heterostructure TFTs, which is adequate for the operation of next-generation microelectronic devices. These results are presumed to be due to the unique electronic structure of amorphous multilayered ZnOSnO₂ heterostructure film consisting of ZnO, SnO₂, and ZnO-SnO₂ interface layers. [ABSTRACT FROM AUTHOR]