A Dissolved Oxygen (DO) sensor has been designed and fabricated on an 8.5 x 22.5 mm Alumina substrate using thick film technology. The structure of the sensor device consisted of AgPd working/counter electrode, Ag/AgCl reference electrode, RuO2active layer, KCl electrolyte, and TiO2membrane. Formation of the Ag/AgCl reference electrode was done by chlorination of Ag layer using FeCl3, and the TiO2membrane was formed by screen printing of TiO2paste. Measurement was done to study the sensor’s performance based from the current-voltage characteristics between 1.1 – 1.6 V. The results showed that a stable diffusion current was obtained when the input voltage was 1.4 V, resulting in the best sensor performance with a sensitivity of 0.560 μA l/mg and a stable step response time of 4 min. The device showed highly potential to be used as candidate for online water quality monitoring system.
Experience with polymer thick film technology