Enhanced Sensing Characteristics in MEMS-based Formaldehyde Gas Sensor

CoRR 01/2008; abs/0802.3072.
Source: DBLP


This study has successfully demonstrated a novel self-heating
formaldehyde gas sensor based on a thin film of NiO sensing layer. A new
fabrication process has been developed in which the Pt micro heater and
electrodes are deposited directly on the substrate and the NiO thin film
is deposited above on the micro heater to serve as sensing layer. Pt
electrodes are formed below the sensing layer to measure the electrical
conductivity changes caused by formaldehyde oxidation at the oxide
surface. Furthermore, the upper sensing layer and NiO/Al2O3
co-sputtering significantly increases the sensitivity of the gas sensor,
improves its detection limit capability. The microfabricated
formaldehyde gas sensor presented in this study is suitable not only for
industrial process monitoring, but also for the detection of
formaldehyde concentrations in buildings in order to safeguard human

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