Pure semiconducting Ga2O3 thin films show a reaction to reducing gases as w
ell to oxygen variations at operation temperatures between 600 degrees C-90
0 degrees C. By applying surface modifications with catalytically active ox
ides like La2O3 or CeO2, a complete suppression of the reaction to reducing
gases in oxygen-rich atmospheres could be achieved, yielding devices that
only respond to the oxygen content. By an analysis of the desorbing gases w
ith NIR-Spectroscopy, varying production rates of carbon oxides and unsatur
ated carbohydrates were observed. A modification with manganese oxide yield
ed complete gas-insensitive devices, which still show a thermal-activated c
onductivity. This effect can he used for temperature compensation purposes.
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