Bending tests of carbon nanotube thin-film transistors on flexible substrate
Bending tests of carbon nanotube thin-film transistors on flexible substrate have been characterized in this paper. The device channel consisting of dense, aligned, 99% pure semiconducting single-walled carbon nanotubes (SWCNT) are deposited using dip-coat technique on sacrificial substrate and then transferred on to the device substrate. Ink-jet printing technique is used to form the source, drain and gate electrodes using silver ink. A novel source-drain contact formation using wet droplet of silver ink prior to CNT thin-film application has been developed to enhance source-drain contact with the CNT channel. Bending test data on CNT-TFT test structures show minimal change (less than 10%) in their performance. To reduce the device performance variation due to bending, flexible electronic circuit is designed such that vertical device orientation is used for backward bending and horizontal orientation is used for forward bending.