Ruales Ortega, M: Heated Ceramic Sensors to Detect Halogen G

The , construction and optimization of a low power-high temperature heated ceramic sensor to detect leaking of halogen gases in refrigeration systems are presented. The manufacturing process was done with microelectronic assembly and the Low Temperature Co-fired Ceramic (LTCC) technology. Four basic sensor materials were fabricated and tested (Lithium Silicate, Sodium Silicate, Potassium Silicate, and Calcium Silicate). The evaluation of the sensor material, sensor size, operating temperature, bias voltage, electrodes size, firing temperature, gas flow, and sensor life was done. All sensors respond to the gas showing stability and reproducibility. The sensors were analyzed, modeled and the response to the gas was divided in surface diffusion and bulk diffusion within the sensor. The theoretical results obtained by the modeling of the sensor were in agreement with the experimental values.