High sensitive micro thermal conductivity detector with sandwich structure

This paper reports a high sensitive micro thermal conductivity detector (μTCD) with sandwich structure, which is composed of glass substrate, silicon-on-insulator (SOI) with micro channels and glass with micro channels. A suspended cross-mesh structure includes a Pt thermistor protected by two SiNx layers and a cross-mesh support made of top silicon of SOI, and it is released by deep reactive ion etching (DRIE) substrate silicon of SOI. Our new μTCD has the better reliability, smaller excess dead volume and less process time compared to the state of the art. Experimental results show that this detector demonstrates a high sensitivity without pre-concentrator.