GAS DETECTOR WITH LOW-COST MICROMACHINED FIELD-IONIZATION TIPS

This letter describes a low-cost fabrication of held ionization tips f or gas detection application, The method addresses same of the most im portant aspects of micro gas detector technology; namely, manufacturin g cost, sensitivity and reproducibility, The tips were designed and fa bricated with Standard microfabrication technologies: thermal oxidatio n, wet chemical etching and sputtering. However, the major achievement is the use of a low-resolution mask to position the tips very closely to a second electrode in a self-aligned process. In our investigation , the vaporized CH3COOH was selected as the sample gas to measure the detector sensitivity. The minimum-measured sensitivity of the detector is 14 ppm and this was accomplished at an operating voltage of only 5 V.