Electrical and Photosensivity Characteristics of Hybrid/Composite ZnO Nanorod Transistors

This letter shows the bottom-contact-type transistors with free-standing ZnO NR arrays that were fabricated by hydrothermal decomposition. The NR arrays were selectively grown in the channel layer between the source and drain electrodes in order to enhance the electrical characteristics of the hybrid/composite NR transistors. The on/off current ratio and mobility of hybrid/composite NR transistors (3.98 × 10⁵; 0.66 cm²·V^-1·s^-1) are higher than those of the ZnO film transistors (2.2 × 10⁴; 0.29 cm²·V^-1·s^-1). The relative photoconductivity (γ) and photoresponsivity (R) of hybrid/composite NR transistors (γ_NR = 4.6 × 10⁵; R = 0.2 A/W) performed better than conventional film transistors (γ_film = 2.27 × 10²; R = 1.06 × 10^-3 A/W) in the depletion region (V_DS = -19 V; V_GS = 50 V ).