Fig. 2.
Correlation between the transport characteristics and morphological properties of DPP2T/PS blend films. (A) Representative room-temperature transfer characteristics of pure DPP2T and DPP2T/PS FETs under a VDS of −60 V. The channel length and width of the devices are 40 μm and 1 mm, respectively. (B) Hole μ-values of FETs fabricated with DPP2T/PS blend films of various concentration ratios. The curved line indicates the trend in the hole μ-value observed with the variation of the DPP2T concentration. The vertical lines (whiskers) indicate the range from the 10th to the 90th percentile. The minimum and maximum values are indicated by asterisks. (Inset) Schematic illustration of the device structure. (C) TEM images of DPP2T/PS films of various concentration ratios. These images show the evolutionary phase change of the DPP2T in the PS matrix as the concentration of DPP2T increases. (Scale bar, 200 nm.)