The sensitivity of conventional ion-sensitive field-effect transistors (ISFETs) is limited to 59 mV/pH, which is the maximum detectable change in electrochemical potential according to the Nernst equation. Here we demonstrate a transducer based on a ZnO dual-gate field-effect transistor that breaches this boundary. To enhance the response to the pH of the electrolyte, a self-assembled monolayer has been used as a top gate dielectric. The sensitivity scales linearly with the ratio between the top and bottom gate capacitances. The sensitivity of our ZnO ISFET of 22 mV/pH is enhanced by more than two orders of magnitude up to 2.25 V/pH.
Beyond the Nernst-limit with dual-gate ZnO ion-sensitive field-effecttransistors / M., Spijkman; E. C. P., Smits; J. F. M., Cillessen; Biscarini, Fabio; P. W. M., Blom; D. M., de Leeuw. - In: APPLIED PHYSICS LETTERS. - ISSN 1077-3118. - 98:4(2011), pp. 043502--. [10.1063/1.3546169]
Beyond the Nernst-limit with dual-gate ZnO ion-sensitive field-effecttransistors
BISCARINI, FABIO;
2011
Abstract
The sensitivity of conventional ion-sensitive field-effect transistors (ISFETs) is limited to 59 mV/pH, which is the maximum detectable change in electrochemical potential according to the Nernst equation. Here we demonstrate a transducer based on a ZnO dual-gate field-effect transistor that breaches this boundary. To enhance the response to the pH of the electrolyte, a self-assembled monolayer has been used as a top gate dielectric. The sensitivity scales linearly with the ratio between the top and bottom gate capacitances. The sensitivity of our ZnO ISFET of 22 mV/pH is enhanced by more than two orders of magnitude up to 2.25 V/pH.
Pubblicazioni consigliate
I metadati presenti in IRIS UNIMORE sono rilasciati con licenza Creative Commons CC0 1.0 Universal, mentre i file delle pubblicazioni sono rilasciati con licenza Attribuzione 4.0 Internazionale (CC BY 4.0), salvo diversa indicazione.
In caso di violazione di copyright, contattare Supporto Iris
