Characterization of amorphous multilayered ZnO-SnO2 heterostructure thin films and their field effect electronic properties

摘要

Multilayered ZnO-SnO heterostructure thin films were produced using pulsed laser ablation of pie-shaped ZnO-SnO oxides target, and their structural and field effect electronic transport properties were investigated as a function of the thickness of the ZnO and SnO layers. The films have an amorphous multilayered heterostructure composed of the periodic stacking of the ZnO and SnO layers. The field effect electronic properties of amorphous multilayered ZnO-SnO heterostructure thin film transistors (TFTs) are highly dependent on the thickness of the ZnO and SnO layers. The highest electron mobility of 37 cm/V s, a low subthreshold swing of a 0.19 V/decade, a threshold voltage of 0.13 V, and a high drain current on-to-off ratio of ∼10 obtained for the amorphous multilayered ZnO(1.5 nm)-SnO(1.5 nm) heterostructure TFTs. These results are presumed to be due to the unique electronic structure of an amorphous multilayered ZnO-SnO heterostructure film consisting of ZnO, SnO, and ZnO-SnO interface layers.