A novel Al2O3-based semiconductor gas sensor for CO and CH4 detection

A new type of semiconductor gas sensor fabricated on an alumina substrate for CO and CH4 detection has been developed. The alumina substrate was obtained by an anodizing method companying with micromachining to form patterned structure. Gas sensitive material was made of nano-sized SnO2 powder prepared by a chemical precipitation method. Au (0.048 wt.%) and I'd (0.3 wt%) were doped to SnO2 powder to increase sensitivity to CO and CH4, respectively. The heating power and sensing performance were measured with an automatic test system. The results show that the sensors have remarkable responses and certain selectivity to the target gases. Our study demonstrates that alumina substrate can be successfully applied in sensor micromachining technology.