Optimization of ammonia-sensitive metal-oxide-semiconductor structures with platinum gates

doi:10.1016/0250-6874(87)80075-6

Sensors and Actuators

Volume 11, Issue 4, 6 May 1987, Pages 349-365

https://doi.org/10.1016/0250-6874(87)80075-6 Get rights and content

Abstract

Ammonia gas-sensitive MOS capacitors with platinum as a thin active metal gate have been studied. The influence of parameters such as the thickness and area of the platinum film on the ammonia sensitivity was investigated. Thicknesses of about 10 to 30 nm of platinum were found to be favourable for a large response to small ammonia concentrations. It was further observed that with aluminium as a thick contact material, the response to ammonia was independent of the area of the platinum film. Theoretical and experimental C(V curves were compared to elucidate the mechanism behnd the ammonia sensitivity. it is concluded that the sensitivity arises from the thin catalytic Pt film.

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Optimization of ammonia-sensitive metal-oxide-semiconductor structures with platinum gates

Abstract

Sensors and Actuators

Anal. Chim. Acta

Anal. Chim. Acta

Sensors and Actuators

Thin Solid Films, 145

Surface Sci.

J. Catalysis

Chem. Phys. Lett.