Abstract: ZnO nanowires with (002) oriented direction was synthesized via modified CVD method. Bottom-up assembly including photolithography/lift off was employed to fabricate gas sensor based on single ZnO nanwire with 50-300 nm in diameter and 2-10 μm in length. The as-prepared device showed gas sensitivities of 1.3 and 1.2 to oxygen and ethanol gases with concentration of 500 μL·L-1 at room temperature, and the corresponding temporal responses were 10 and 5 s, respectively. The improved gas sensing properties were attributed to the enhancement of the current-induced heating on the quasi-one-dimensional nanostructure.

Key words: ZnO, Nanowire, Gas sensor