Versatile α,ω-Disubstituted Tetrathienoacene Semiconductors for High Performance Organic Thin-Film Transistors

摘要

Facile one-pot [1 + 1+2] and (2 + 1 + 1] syntheses of thieno[3,2-b]-thieno[2',3':4,5]thieno[2,3-d]thiophene (tetrathienoacene; TTA) semiconductors are described which enable the efficient realization of a new TTA-based series for organic thin-film transistors (OTFTs). For the perfluorophenyl end-functionalized derivative DFP-TTA, the molecular structure is determined by single-crystal X-ray diffraction. This material exhibits n-channel transport with a mobility as high as 0.30 cm~2V~(-1)s~(-1) and a high on-off ratio of 1.8 × 10~7. Thus, DFP-TTA has one of the highest electron mobilities of any fused thiophene semiconductor yet discovered. For the phenyl-substituted analogue, DP-TTA, p-channel transport is observed with a mobility as high as 0.21 cm~2V~(-1)s~(-1). For the 2-benzothiazolyl (BS-) containing derivative, DBS-TTA, p-channel transport is still exhibited with a hole mobility close to 2 × 10~(-3)cm~2V~(-1)s~(-1). Within this family, carrier mobility magnitudes are strongly dependent on the semiconductor growth conditions and the gate dielectric surface treatment.