A technological process for batch wafer scale fabrication of electrochemical sensors based on single-walled carbon nanotube (SWCNT) field effect transistors (FETs) is presented. The fabrication of the carbon nanotube (CNT)-FETs is based on the chemical vapor deposition synthesis of the SWCNTs on predefined catalytic areas combined with standard microelectronic processes. Optical lithography is the only patterning method to be used. A fabrication yield close to 20% is achieved, which allows delivering thousands of CNT-FETs per wafer. An additional process to passivate the CNT-FETs is introduced to enable electrochemical sensing applications. (C) 2010 American Vacuum Society. [DOI: 10.1116/1.3504527]