S. Nakata et al., Non-linear dynamic responses of a semiconductor gas sensor: Evaluation of kinetic parameters and competition effect on the sensor response, SENS ACTU-B, 76(1-3), 2001, pp. 436-441
A novel gas-sensing system based on a dynamic non-linear response is report
ed. A sinusoidal temperature change is applied to a semiconductor gas senso
r, and the resulting conductance of the sensor is analyzed. The sensor resp
onse changes characteristically depending on the composition of the gas spe
cies and is analyzed by fast Fourier transformation (FFT). Not only the ind
ividual concentrations of samples but also the competition effect on the se
nsor responses to gaseous mixtures are evaluated by the higher harmonics of
FFT. The physicochemical parameters on the sensor response are estimated b
ased on information fi om the non-linear response under the application of
temperature modulation. The competition effect on the response to two sampl
es is discussed in relation to the kinetics of gas molecules on the semicon
ductor surface. (C) 2001 Elsevier Science B.V. All rights reserved.