DNA sensing by field-effect transistors based on networks of carbon nanotubes

• Main Authors: Rogers, John A., Dong, Xiaochen, Ho, Xinning, Lee, Pooi See, Kasim, Johnson, Shen, Zexiang, Mhaisalkar, Subodh Gautam, Gui, Ee Ling, Li, Lain-Jong, Zhang, Keke, Xu, Yangping
• Other Authors: School of Materials Science & Engineering
• Format: Article
• Language: English
• Published: 2012
• Subjects: DRNTU::Engineering::Materials
• Online Access: https://hdl.handle.net/10356/94712; http://hdl.handle.net/10220/8506
• Institution: Nanyang Technological University

We report on the sensing mechanism of electrical detection of deoxyribonucleic acid (DNA) hybridization for Au- and Cr-contacted field effect transistors based on single-walled carbon nanotube (SWCNT) networks. Barrier height extraction via low-temperature electrical measurement provides direct evidence for the notion that the energy level alignment between electrode and SWCNTs can be affected by DNA immobilization and hybridization. The study of location-selective capping using photoresist provides comprehensive evidence that the sensing of DNA is dominated by the change in metal−SWCNT junctions rather than the channel conductance.