Differential injection analysis based on backside-contacted ISFETs

In this paper a differential injection analysis (DIA) based on ISFETs is presented. The method consists of differential measurements in two parallel micro-cells with identical ISFET sensors connected in the output port. Sample is injected in the first cell as in conventional FIA systems, while in the second cell it is injected as reference buffer. In this way, a simple method for differential measurements is implemented avoiding the need of a reference electrode. By using BSC-ISFET technology integrated with tubular microcell, parallel cells with identical ISFETs are obtained in batch-fabrication.