Tuning the contact resistance in organic thin-film transistors with an organic–inorganic hybrid interlayer

We demonstrated the tunable contact resistance in pentacene thin film transistor (TFT) by inserting an organic–inorganic hybrid interlayer between Au electrode and pentacene layer. The contact resistance of pentacene-TFT varies with concentration of pentacene-TFT varies with concentration of MoO x in organic–inorganic hybrid interlayer. MoO x in organic–inorganic hybrid interlayer. The contact resistance of the device with 55 wt% MoO x doped pentacene interlayer is about 7.8 times smaller than that of device without interlayer at the gate voltage of −20 V. Comparing the properties of pentacene-TFT without interlayer, the performance of the pentacene-TFT with 55 wt% MoO x doped pentacene was significantly improved: saturation mobility increased from 0.39 to 0.87 cm 2 /V s, threshold voltage reduced from −21.3 to −7.2 V, and threshold swing varied from 3.75 to 1.39 V/dec. Our results indicated that the organic–inorganic hybrid interlayer is an effective way to improve the performance of p -channel OTFTs.