Figure 10: (a) Optical microphotos (size of 120 μm × 92 μm) of polyethylene after PIII treatment. The wave structure appears after PIII treatment while untreated film is smooth. (b) AFM image of polyethylene surface after PIII. The lateral scale is 30 μm (left image) and 10 μm (right image). Vertical scale is 1 μm. The average wave’s period is 2.3 μm.