CMOS ISFET-Based Structures for Biomedical Applications

Authors: B. Palán, K. Roubík, M. Husák and B. Courtois

Citation

Palan B, Roubik K, Husak M, Courtois B. CMOS ISFET-Based Structures for Biomedical Applications. In Microtechnologies in Medicine and Biology, 1st Annual International IEEE-EMBS Special Topic Conference 2000; 502-506.

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CMOS ISFET-Based Structure For Biomedical Applications

Published in IEEE Xplore

Abstract

The miniaturization and integration of biomedical sensors is of key importance for improved diagnosis and therapy in the future. These devices integrated monolithically on the same chip together with low-power electronics are suitable for implantable “in vivo” monitoring of arterial blood pH, pCO2 or pO2 changes. This paper deals with the design, fabrication and experimental evaluation of ISFET-based structures realized in an unmodified commercial submicron 0.6μm CMOS technology. The compatibility study of pH ISFET chemical devices with CMOS circuits is described. Some technologydriven problems associated with using this submicron proces for the chemical microsensors are reported. Comparison of our fabricated structures with previously published ISFETs using unmodified standard CMOS technology is given. Research goals are to develop fully integrated CMOS compatible ion-sensitive ISFET devices for implantable biomedical microsystems.

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