Journal
MICROELECTRONICS JOURNAL
Volume 37, Issue 10, Pages 1105-1114Publisher
ELSEVIER SCI LTD
DOI: 10.1016/j.mejo.2006.05.001
Keywords
ion sensitive field effect transistor (ISFET); pH sensor; temperature compensation
Ask authors/readers for more resources
An integrated and new interface circuit with temperature compensation has been developed to enhance the ISFET readout circuit stability. The bridge-type floating source circuit suitable for sensor array processing has been proposed to maintain reliable constant drain-source voltage and constant drain current (CVCC) conditions for measuring the threshold voltage variation of ISFET due to the corresponding hydrogen ion concentration in the buffer solution. The proposed circuitry applied to Si3N4 and Al2O3-gate ISFETs demonstrate a variation of the drain current less than 0.1 mu A and drain-source voltage less than 1 mV for the buffer solutions with the pH value changed from 2 to 12. In addition, the scaling circuitry with the V-T temperature correction unit (extractor) and LABVIEW software are used to compensate the ISFET thermal characteristics. Experimental results show that the temperature dependence of the Si3N4-gate ISFET sensor improved from 8 mV/degrees C to less than 0.8 mV/degrees C. (c) 2006 Elsevier Ltd. All rights reserved.
Authors
I am an author on this paper
Click your name to claim this paper and add it to your profile.
Reviews
Recommended
No Data Available