Automation of 1 tΩ to 100 tΩ ultra-high resistance measurements at NIST

The automation of ultra-high resistance measurements at the National Institute of Standards and Technology (NIST) in the range 1 TOmega to 100 TOmega has been completed with the use of a programmable XY positioning system to facilitate the guarded connection of multiple standard resistors to an automated dual-source bridge. Automated guarded switching that is immune to leakages to ground is critical to the characterization of standard resistors and transfer standards in this range.