V. Ambrazeviciene et al., GAS-SENSING PROPERTIES OF CHEMICALLY DEPOSITED SNOX FILMS DOPED WITH PT AND SB, Sensors and actuators. B, Chemical, 17(1), 1993, pp. 27-33
The influence of Pt and Sb additives on the gas sensitivity of chemica
lly deposited SnO(x) films has been investigated. The temperature depe
ndence of the resistance change and response time of SnO(x) to various
gases in the air has been measured. Particular attention is paid to t
he CO and H-2 sensitivities at an operating temperature t less-than-or
-equal-to 100-degrees-C. The non-doped and Sb-doped SnO(x) films show
a low gas sensitivity at t almost-equal-to 100-degrees-C. The resistan
ce change and response time tau of Pt-doped films depend on the anneal
ing temperature. The SnO2:Pt Samples annealed at low temperature (t(a)
less-than-or-equal-to 400-degrees-C) are gas sensitive but slow (tau
= 50-500 s) at 100-degrees-C. Annealing at t(a) greater-than-or-equal-
to 700-degrees-C leads to a considerable reduction of the gas sensitiv
ity of Pt-doped films. The SnO(x) samples doped simultaneously with Pt
and Sb show a high sensitivity to CO or H-2 and a fast response and r
ecovery at t less-than-or-equal-to 100-degrees-C (tau less-than-or-equ
al-to 2 s). These samples prove to be sensitive to ethanol, acetaldehy
de and acetic acid, but not to O2, CO2, SO2 and NO(x).