Ambipolar thin-film transistors based on organic semiconductor blend

Ambipolar thin-film transistors are fabricated employing p-channel (2-decyl-7-phenylbenzo[b]benzo [4,5]thieno [2,3-d]thiophene; Ph-BTBT-C10) and n-channel (N,N'-di-n-octyl-3,4,9,10-perylenetetracarboxylic diimide; PTCDI-C8) semiconductors in bilayer and bulk heterojunction architecture. Bilayer organic semiconductors with small thickness of the first layer exhibit ambipolar device characteristics with relatively poor electrical performance. On the other hand, bulk heterojunction organic thin-film transistors (OTFTs) with optimized blend ratio exhibited higher ambipolar charge transport properties with carrier mobility as high as 0.22 and 0.038 cm(2) V-1 s(-1) for hole and electron, respectively. Complementary-like inverters fabricated based on optimized bulk heterojunction OTFTs show high transfer gain of 96.