Organic thin film transistors with a SiO_2/SiN_x/SiO_2 composite insulator layer

摘要

We have investigated a SiO_2/SiN_x/SiO_2 composite insulation layer structured gate dielectric for an organic thin film transistor (OTFT) with the purpose of improving the performance of the SiO_2 gate insulator. The SiO_2/SiN_x/SiO_2 composite insulation layer was prepared by magnetron sputtering. Compared with the same thickness of a SiO_2 insulation layer device, the SiO_2/SiN_x/SiO_2 composite insulation layer is an effective method of fabricating OTFT with improved electric characteristics and decreased leakage current. Electrical parameters such as carrier mobility by field effect measurement have been calculated. The performances of different insulating layer devices have been studied, and the results demonstrate that when the insulation layer thickness increases, the off-state current decreases.