Dependence of bias stress on hydrophobicity of gate insulator in solution-processed organic thin-film transistors

We demonstrated the effect of the hydrophobicity of a gate insulator on the bias stress in a solutionprocessed organic thin-film transistor (OTFT). Without changing the surface morphology, only the hydrophobicity of the gate insulator was systematically tailored to achieve the electrical stability of the OTFT against the bias stress. The shift of the threshold voltage (V_TH) by the gate bias stress was found to decrease with increasing the hydrophobicity of the gate insulator. The shift of V_TH in the optimized OTFT was as small as -1.09 V under the gate bias stress for 1000 s.