Blend film OFETs

As compared with film growth at room temperature, an inereased mobility is found for the higher substrate temperature and a lurther inerease is realised by lowering the surface energy with OTS. This increase of mobility was reported for unipolar OFETs [43] and is also valid for these blends. Interestingly, for all treatments balaneed mobilities are found at about 25% C o eontent. 

A functionalized sensor with structure as shown in Fig. 7.15b had higher sensitivity and response speed. In this functionalized OFET sensor, 15 nm of 6PTTP6 and HO6OPT semiconductor blend, serving as a functionalized receptor layer, was coevaporated on top of a 35 nm 6PTTP6 film. 

This supports the theories of crystalline-crystalline blend behavior discussed in Section 8.2.1. However, it should be noted that if the polymer is too crystalliz-able, it is possible for it to crystallize first leading to film microstructures dominated by the polymer and OFET mobilities closer to that of the neat polymer than that of the acene molecule. 

Most of the discussion thus far has focused on thin films produced by spin casting. However, one goal of these composite systems, and the acene blends in particular, is to improve processability during printing, especially inkjet printing. TIPS-pentacene-based OFETs fabricated by inkjet-printed semiconductor have been... 

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