Integration of MOX gas sensors on polyimide hotplates

Abstract

In this communication, we report on the integration of metal-oxide gas sensors on polymeric micro-hotplates made on polyimide and silicon substrates. Low-power consumption micro-hotplates with platinum electrodes and heaters were fabricated on polyimide membranes. Their thermal behavior was optimized using temperature probing at the micro-scale level coupled with thermal simulations. Tin oxide thick films were successfully integrated on these polyimide micro-hotplates using the drop coating technique. The annealing process of the tin oxide drops on the polyimide substrate was investigated and gas measurements are presented. Compared to the polyimide hotplates on silicon substrates, the hotplates made on polyimide sheets are simpler to process and more robust, and therefore, they are more suitable for the integration of metal-oxide films. Finally, a wafer level packaging technique using multiple polyimide layers was developed and led to a polymeric platform for metal oxide sensors. The technology is also promising for the integration of polyimide humidity sensors, of resistive and capacitive gas-sensitive polymeric films to realise fully flexible gas sensor arrays.

A low cost polyimide based metal oxide film RH sensor

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Ultra-sensitive, low-power and flexible H<inf>2</inf>S sensors based on palladium nanoparticle-coated metal oxide nanowires

“…Even though their gas sensing performances showed rapid response and high sensitivity to toxic gases, integration and surface functionalization of nanomaterials are still challengeable because of the complicated steps and imperfect contact between nanomaterials and metal electrodes [3]. For instance, currently used methods for fabrication of nanomaterials based chemical sensors on plastic substrate usually require transfer technology, which include the process of nanomaterial separation from growth substrate and transfer to device substrate [4][5][6]. Furthermore, time-consuming step (e.g.…”

Micro-heater filament on polyimide membrane for gas sensor applications

“…Furthermore, robustness and flexibility is increased when fabricated on polyimide as compared to microhotplates on silicon with membranes made of dielectric layers [7].…”