Authors: B. Palán, K. Roubík, M. Husák and B. Courtois
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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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.
 C. Cané, A. Gotz, A. Merlos, I. Garcia, A. Errachid, P. Losantos, E. Lora-Tamayo, “Multilayer ISFET membranes for microsystems applications,” Sensors and Actuators B, 35-36, pp. 136-140, 1996.
 P. Bergveld, “Development of an ion-sensitive solid-state device for neurophysiological measurements, ” IEEE Trans. On Biomedical Engineering, 17, pp.70-71, 1970.
 T. Matsuo and M. Esashi, “Methods of ISFET fabrication, ” Sensors and Actuators, 1, pp.77-96, 1981.
 L. Bousse, H.H. Van Den Vlekkert, N.F. De Rooij,, “Hysteresis in Al2O3 gate ISFETs, ” Sensors and Actuators B, 2, pp.103-110, 1990.
 A.S. Poghossian, “The super-nerstian pH sensitivity of Ta2O5 gate ISFETs, ” Sensors and Actuators B, pp.367-370, 1992.
 L. Bousse, J. Shott, J.D. Meindl, “A process for the combined fabrication of ion sensors and CMOS circuits,” IEEE Electron Device Letters, 9, 1, pp.44-46, 1988.
 C. Cane, I. Gracia, A. Merlos, M. Lozano, E. Lora-Tamayo, J. Esteve, “Compatibility of ISFET and CMOS technologies for smart sensors” Proc. 6th Int. Conf. Solid State Sensors and Actuators (Transducers ’91), San Francisco, CA, USA, pp. 225-228, 1991.
 T.C.W. Yeow, M.R. Haskard, D.E. Mulcahy et al., “A very large integrated pH-ISFET sensor array chip compatible with standard CMOS processes, ” Sensors and Actuators B, 44, pp. 434-440, 1997.
 J. Bausells, J. Carrabina, A. Errachid, A. Merlos, “Ion-sensitive transistors fabricated in a commercial CMOS technology,” Eurosensors XII Conf. proceedings, 13-16 September, Southampton, pp.167-170, 1998.