A high-performance TCD monolithically integrated with a gas separation column

We present the design, fabrication and experimental evaluation of a unique micro gas chromatography (μGC) column with an integrated micro thermal conductivity detector (μTCD). The resistors are dry released to form 170μm diameter coils. The high isolation of the sensing element requires only 13mW and sub-6ms to ramp up to 100°C and in turn an improved sensitivity by an order of magnitude over our previously reported designs. The chip incorporates a 2-port design approach and a device size of 2cm×4cm. Fabricated using a four-mask process, the resistors and microfluidics are independently processed on borofloat and silicon wafers, respectively, and subsequently anodic bonded. The separation column is static coated without damage to the resistors. The coated column-detector chip has successfully separated a representative hydrocarbon mixture in less than 2 minutes.