PH Sensor, PH measurement method, ION sensor and ION concentration measurement method

摘要

A pH sensor includes a reference electrode (1) including a p-channel field effect transistor (FET) having drain (13), source (14) and gate (10) whose gate (10) includes a diamond surface (12) having a hydrogen ion insensitive terminal, and a working electrode (2). A pH measuring method comprises bringing a liquid to be measured into contact with a reference electrode (1) including a p-channel field effect transistor having drain (13), source (14) and gate (10), whose gate (10) includes a diamond surface (12) having a hydrogen ion insensitive terminal, and a working electrode (2), and measuring pH of the liquid to be measured based on outputs of the reference electrode (1) and the working electrode (2). An ion sensor comprises a reference electrode (1) including a first p-channel field effect transistor in which a semiconductor surface contains diamond, and a working electrode (2) including a second p-channel FET whose gate portion has a different surface terminal. An ion concentration measurement method comprises bringing a liquid to be measured into contact with such a reference electrode (1) and working electrode (2), and measuring the ion concentration of the liquid to be measured based on outputs of the reference electrode (1) and the working electrode (2).