High-Performance n-Channel Organic Thin-Film Transistor for CMOS Circuits Using Electron-Donating Self-Assembled Layer

We introduce an electron-donating self-assembled monolayer (SAM) to improve the performance of solution-processed n-channel organic thin-film transistor (OTFT) using an organic semiconductor (OS) of an N, N
^'
bis-(octyl-)-dicyanoperylene-3,4:9,10-bis(dicarboximide) (PDI-8CN
₂
). The OTFTs without SAM, with electron-withdrawing, and electron-donating layers, exhibited field-effect mobility of 0.02, 0.01, and 0.33 cm
²
/(V·s), respectively. The electron-donating thiophenol layer on source/drain electrodes shows a small injection barrier of 0.05 eV to the n-type OS and thus, exhibited field-effect mobility of 0.33 cm
²
/(V·s) and threshold voltage of -1.1 V.