Ion sensor based on differential measurement, and production method

Abstract

The invention relates to an ion sensor based on differential measurement, comprising an ISFET/REFET pair, wherein the REFET is defined by a structure formed by an ISFET covered by a micro-reservoir containing an internal reference solution. The sensor comprises: a first and a second ion-selective field effect transistor; an electrode; a substrate on the surface of which the two transistors, connection tracks and the electrode are integrated; and a structure adhered to the first ion-selective field effect transistor, creating a micro-reservoir on the gate of said first transistor, said micro-reservoir having a micro-channel connecting the micro-reservoir with the exterior, and said micro-reservoir being filled with the reference solution