Threshold voltage drift of FET sensor arrays with different gate insulators

Threshold voltages of EISFET exhibit temporal drift that is a major challenge for electronic detection of DNA. We fabricated a series of EISFET arrays and experimentally studied absolute drift, relative drift and settling times of their threshold voltages. Comparing different gate insulator materials, we found best drift performance with Si3N4, TiO2 or SiO2 insulators, depending on the salt concentrations used in the electronic measurements.