Development of materials and printing methods for fabrication of thin-film transistors on flexible substrates

J.W. Zhao, Y.L. Gao, W.B. Gu, J. Lin, Z. Chen, Z. Cui
Suzhou Institute of Nanotech and nano-bionics, Chinese Academy of Sciences, CN

Keywords: all-printed, thin film transistors, flexible substrates, carbon nanotubes


In the present work, we attempted to put together a suite of technologies for printing TFTs on flexible substates. The ink materials we investigated include optimized SCNT inks as printable semiconductors, development of composite ion-gel as dielectrics and nanosilver ink as conductors. The printing methods we investigated include inkjet printing, aerosol jet printing and a hybrid with nanoimprinting. Large area source and drain electrode patterns were first fabricated on flexibe substrates by a hybrid printing method, and then SCNT thin films were deposited on the channel of TFT devices by ink-jet printing. Subsequently, the silver side-gate electrode and ion gel dielectric layer were deposited by aerosol jet printing. Figure 1 shows optical images of printed TFT and its electrical properties. The all-printed TFT has the effective mobility up to 1.3 cm2/Vs and on/off ratio up to 103. The detailed investigations will be presented in the paper.