Resolving Unusual Gate Current and Dielectric Breakdown of Solution Processed Carbon Nanotube Thin Film Transistor

The traditional design of solution processed single-walled carbon nanotube (SWCNT) thin film transistors (TFTs) suffers from high leakage currents and are prone to dielectric breakdowns. In this paper, we report the proof of concept of an improved structure for a solution processed SWCNT based TFT. The improved structure TFT has 11,429 times lower gate leakage current than a traditional design TFT of the same dimensions in the on state and exhibits no dielectric breakdown. The gate leakage current in the improved structure is reduced and the dielectric breakdown is resolved by a simple patterning of the SWCNT layer and increasing the thickness of the dielectric layer. In order to take advantage of solution based fabrication techniques, the active layer and the electrodes are fabricated by solution based depositions. The improved structure TFT has a mobility of 0.3 cm
²
V
^-1
s
^-1
and an on/off ratio of approximately 2640. The mobility and on/off ratio can be further improved in the future by increasing the incubation time in the SWCNT solution. In the future, the active and dielectric layers of this structure will be printed and the TFT will be miniaturized, to produce entirely printed SWCNT TFTs and circuits.