Preconcentrator-based sensor mu -system for low-level benzene detection

In this paper, a preconcentrator-based sensor mu -system for low level benzene detection is presented. It consists of a spiral-shaped mu -reconcentrator with dimensions of 10 cm * 300 mu m * 300 mu m, followed by a mu -hotplate sensor matrix. The mu -preconcentrator was fabricated on a silicon wafer by means of DRIE and anodic bonding techniques. To obtain the concentration factor of the fabricated devices, a GC/MS: Shimadzu-QP5000 equipment was used. The results obtained showed excellent repeatability and preconcentration factors up to 286. A considerable improvement (1500%) in the sensor responses was achieved with Pd doped SnO/sub 2/ sensors. The small size of the manufactured devices enables their incorporation in an integrated GC/MS gas sensor system.Anglai