Self-aligned carbon nanotube thin-film transistors on flexible substrates with novel source-drain contact and multilayer metal interconnection

This paper presents the development and characterization of self-aligned carbon nanotube thin-film transistors (CNT-TFT) on flexible substrates. The channel consisting of dense, aligned, 99 pure semiconducting single-walled CNT is deposited using the dip-coat technique on a sacrificial substrate and then transferred on the device substrate. The source, drain, and gate structures are formed by the ink-jet printing technique. A novel source-drain contact formation using wet droplet of silver ink prior to the 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. Moreover, a special multilayer metal interconnection technology is demonstrated for flexible electronics applications. Bending test data on via test structure show change in resistance by less than 5.