ION SENSOR

摘要

Provided is an ion sensor which can be downsized and solidified while ensuring good reproducibility and stability of measurements. An ion sensor comprises first and second ISFETs each provided, at the gate portion thereof, with an ion sensitive film wherein the second ISFET is provided, at the gate portion thereof, with an ion sensitive film having a surface coated with a self-assembled monolayer composed of a material compound having an ion insensitive group which is insensitive to measurement object ions and a material compound having an ion sensitive group which is sensitive to measurement object ions, and the sensitivity of the second ISFET to the measurement object ions is set lower than the sensitivity of the first ISFET to the measurement object ions.