N,N-bis(4-trifluoromethoxybenzyl)-1,4,5,8-naphthalene-tetracarboxylic di-imide was applied to organic semiconductors for bottom-contact thin-film transistors. The carrier mobility was 1.6×10-2 cm2 V-1 s-1, the threshold voltage (VT) was +5.5 V, and the on/off current ratio was 8.6×105. Devices without any further surface treatments were tested in an ambient environment. The threshold voltage shift (ΔVT) was verified by gate bias stress measurements. A prototype compound, N,N-bis(4-trifluoromethylbenzyl)naphthalene-1,4,5,8-tetracarboxylic di-imide, shows direct correlation to the bottom-contact device with the varied molecular structure. [ABSTRACT FROM AUTHOR]