High mobility organic thin-film transistors on plastic substrate

We have fabricated organic thin-film transistors (OTFTs) based on di-n-decyldinaphtho[2,3-b:2′,3′-f]thieno[3,2-b]thiophene (C10-DNTT) on a polyimide gate dielectric coated on a polycarbonate substrate with a bottom-gate, top-contact configuration. Mobilities of the C10-DNTT-based TFTs were as high as 2.4 cm2 V−1 s−1, which are much better than those of the parent dinaphtho[2,3-b:2′,3′-f]thieno[3,2-b]thiophene (DNTT)-based TFTs (mobility ∼ 0.5 cm2/V) fabricated on the same substrate. Compared to the C10-DNTT-TFTs on the conventional Si/SiO2 substrate, the present mobility of C10-DNTT-TFTs are somewhat reduced, which can be attributed to reduced crystallinity on the polyimide gate dielectric, although the crystalline phase on the polyimide is the same as on the Si/SiO2 substrate.