In this study, the gamma ray radiation effect on the characteristics of inkjet-printed semiconducting single-walled carbon nanotubes (sSWCNTs) thin-film transistors (TFTs) is investigated. The devices with top gate dielectrics consisted of BaTiOsub3/sub and poly(methyl methacrylate) (PMMA) were characterized before and after 150 krad sup60/supCo gamma radiation in air. It reveals that the radiation results in a positive threshold voltage shift from -0.5 to 3.6 V (with a drain voltage biased at -1 V). The hysteresis decreases slightly from 1.2 to 0.5 V, indicating that the BaTiOsub3/sub/PMMA dielectric layer effectively encapsulates the sSWCNTs TFTs from absorbing molecules in the environment. Furthermore, the charge pumping current IsubCP/sub is measured with a gate voltage pulsed at 100 kHz. The maximum IsubCP/sub increases from 90 to 140nA, which translates to an increase in the interface trap density from 4.5×10sup11/sup to 1.1×10sup12/sup cmsup-2/supeVsup-1/sup. The charge pumping measurements at the frequency of 10～250 kHz show that the increase of IsubCP/sub induced by radiation is obvious when f30 kHz but is little when f30 kHz, which indicates that the radiation induced charge traps locate near sSWCNTs. The BaTiOsub3/sub/PMMA gate dielectric remains to be a good insulator with a leakage current of less than 60 pA after radiation. Such printed flexible TFTs with the polymer gate dielectric possess similar radiation tolerant compared to convention devices on rigid substrates.
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