Maximum quantity allowed is 999
Solution processed OFETs using DNTT-PMIs
(1) Mix endo-DNTT-PMI (D5153) and polystyrene in 2:1 weight ratio
(2) Dissolve mixed powder in CHCl3 to prepare 1wt% solution
(3) Spin-coat*1 the solution onto cleaned- and UV/O3 treated-n+-Si/SiO2 substrate
(4) Anneal substrates at 200ºC for 10 min under air for converting the precursor to DNTT thin film
(5) Fabricate source and drain electrodes*2 by vacuum deposition of Au
*1 Spin-coating condition: 500rpm × 5s → 2000rpm × 20s
*2 channel length: 20μm or 200μm, channel width: 1000μm
(for exo-DNTT-PMI (D5154) based transistors, see Org. Electron. 2013, 14, 1211.)
Fig. 2 shows polarized optical microscopy (POM) image of DNTT thin film prepared from DNTT-PMI. Image clearly shows polycrystalline film morphology. As shown in Fig.3, fabricated devices show typical p-type characteristics.
Maximum carrier mobility 0.86 cm2/Vs was observed when channel length was 200µm. Carrier mobility was greatly improved to 2.33 cm2/Vs when the channel length was shortened to 20µm.
This high mobility can be assumed to be as following: the source and drain channels were completely filled in single grain, so the carrier transportation barrier caused by grain boundaries reduced.
Fig. 3 Transfer (left) and output (right) curves of OFET device prepared from endo-DNTT-PMI.
Table 1 Summary of OFET properties of DNTT prepared from endo-DNTT-PMI.
