Tuning of electrical characteristics in networked carbon nanotube field-effect transistors using thiolated molecules

The authors examine the effects of adsorption of four thiolated molecules (HS-C10H21, HS-C11H22OH, HS-C10H20COOH, and HS-C2H4C4F9) on the electrical characteristics of single-walled carbon nanotube network FETs (SNFETs). Work function of the electrodes was measured before and after molecule adsorption. Schottky barrier energy extraction for SNFETs was also performed and the results 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, which thus provides an effective methodology for the tuning and performance optimization of these devices in a controllable way. (C) 2007 American Institute of Physics.