Platinum Balanced Cantilever-based Thermal Conductivity Detector for Gas Chromatography Application

In this paper, we present the design, fabrication and experimental evaluation of a platinum balanced cantilever-based TCD. The TCD is fabricated by sandwiching a thin layer of Al2O3 between platinum layers. The residual stress in platinum films were used to keep the cantilever flat. The miniaturization and geometric design of the TCD facilitates high operating temperature of 300 degrees C with a power consumption of 8 mW. The sensor's sensitivity to temperature and flow rate changes was evaluated for several operating temperatures, 105, 140 and 300 degrees C. It revealed that sensitivity to temperature changes decreases as the sensor's operating temperature increases. The TCD was connected to a GC system to compare its detection performance with a standard FID for a hydrocarbon mixture. The platinum balanced TCD also succeeded in detecting 5 ppm of ammonia.