In this work, an integrated thermal gas flow sensor was fabricated and evaluated using a new thermal isolation technique based on a porous silicon membrane over an air cavity in silicon. The fabrication process of a thermal gas flow sensor employing this type of micro-hotplate is described together with the theoretical estimation of the thermal distribution around the heater of the sensor. Experimental results of the thermal isolation achieved are shown. A flow evaluation of the sensor is presented and discussed. All the results obtained are compared with the corresponding ones for an identical sensor using a micro-hotplate made of porous silicon membrane but without the air cavity underneath. The improvement achieved by the air cavity is evaluated.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.