Fig. 2

Channel formation and thickness control of ZnO NW network FET devices. a Magnified optical image of a 6 μm length NW network channel and Al electrodes. The inset is optical micrograph of 10 × 10 array devices with micro-patterned channels. b Scanning electron microscope (SEM) images showing the selective assembly of ZnO NWs to line patterns with diverse line widths of 5, 10, and 20 μm. c AFM image of ZnO NWs network. d Average distribution of height vs pulling speed at different pulling speed of 0.5~ 10 mm min⁻¹. The inset shows the AFM height profile for different pulling speeds of 0.5, 2, 10 mm min⁻¹