Title :
An integrated micro multi-ion sensor using platinum-gate field-effect transistors
Author :
Tsukada, K. ; Miyahara, K. ; Shibata, Y. ; Miyagi, H.
Author_Institution :
Hitachi Ltd., Tokyo, Japan
Abstract :
An integrated micro multi-ion sensor was designed and fabricated for a high-performance ion sensor applicable to clinical analyses. Platinum gate ISFETs (ion-sensitive field effect transistors), which have a platinum block layer for protection from ion migration and dissolution and are compatible with MOSFETs, are used. The sensor chip consists of, two kinds of ion sensors (K/sup +/ and Na/sup +/ ISFETs) and two CMOS unity-gain buffers. The output voltages are equal to the equivalent gate membrane potentials of the integrated ISFETs and show a wide linear dynamic range. The K/sup +/ and Na/sup +/ ISFETs show good chemical responses, including sensitivities, selectivities, and drifts, which are compatible with those of conventional ion-selective electrodes.<>
Keywords :
CMOS integrated circuits; biosensors; electric sensing devices; electrochemical analysis; insulated gate field effect transistors; potassium; sodium; CMOS unity-gain buffers; ISFET; K/sup +/ sensor; Na/sup +/ sensor; Pt-SiO/sub 2/-Si; chemical responses; clinical analyses; drifts; equivalent gate membrane potentials; high-performance ion sensor; integrated micro multi-ion sensor; output voltages; selectivities; sensitivities; wide linear dynamic range; Biomembranes; Chemicals; Clinical diagnosis; Dynamic range; Electrodes; FETs; MOSFETs; Platinum; Protection; Voltage;
Conference_Titel :
Solid-State Sensors and Actuators, 1991. Digest of Technical Papers, TRANSDUCERS '91., 1991 International Conference on
Conference_Location :
San Francisco, CA, USA
Print_ISBN :
0-87942-585-7
DOI :
10.1109/SENSOR.1991.148841
