Flame-deposited semiconducting nanomaterials on microelectronic circuitry exhibit exceptional performance as chemoresistive gas sensors. Current manufacturing technology, however, does not monitor in situ the formation of such nanostructured films even though this can facilitate the controlled and economic synthesis of these sensors. Here, the resistance of such growing films is measured in situ during fabrication to monitor the creation of a semiconducting nanoparticle network for gas sensors.

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... Upon formation of that network, the film resistance drops drastically to an asymptotic value that depends largely on film structure and morphology rather than on its thickness and nanoparticle size. Sb-doped SnO2 sensing films of different morphologies exhibit different characteristic in situ resistance patterns. The above understanding enables the rapid and economic flame-synthesis of thin gas sensors consisting of minimal nanomaterial mass, possessing a tuned baseline resistance and exhibiting excellent response to ethanol vapor.