Study on the Characteristics of the Ruthenium Oxide pH Electrode

摘要

Ruthenium oxide, which fabricated by radio frequency sputtering is used as the sensitive membrane, which shows that the pH sensitivity is very high and has a linear response in different buffer solutions. The pH electrode, which applies the structure of separative structure EGFET(Extended Gate Field Effect Transistor) insteads of the conventional gate ISFET(Ion Sensitive Field Effect Transistor) for reducing the cost of the fabrication and measurement. Unfortunately, the performance of the pH sensor was falsified by the drift and hysteresis. In addition, the total response is composed of the intrinsic response and drift, and the hysteresis effect combines the slow response with drift. Consequently, we would also investigate the drift in the buffer solutions and hysteresis effect in the different paths. In this way, the more accurate sensing properties are obtained by the RuO_x pH electrode.