Abstract
We examine the effects of adsorption of four thiolated molecules (HS-C 10 H 21 , HS-C 11 H 22 OH, HS-C 10 H 20 COOH, and HS-C 2 H 4 C 4 F 9 ) on the electrical characteristics of single-walled carbon nanotube network FETs (SNFETs). Measuring the work function of the electrodes before and after molecule adsorption and performing Schottky barrier energy extraction for SNFETs provide direct evidence that the device characteristics of SNFETs after SAM adsorption are altered primarily due to the change in energy-level alignment between the Au and SWNTs. We also demonstrate that the electrical characteristics of SNFETs can be modified by introducing thiolated heme on Au electrodes and by using the location-selective photo-irradiation method, which provides an effective methodology for the fine-tuning and performance optimization of these devices in a controllable way. © 2008 IEEE.