Hydrogen- and methane-sensing characteristics of Pt- and Pd-SiC Schottky di
odes, fabricated on the same SiC substrate, have been compared and analyzed
as a function of hydrogen partial pressure and temperature by I-V and Delt
aI-t methods under steady-state and transient conditions at high temperatur
e. The effects of the gas adsorption on the parameters such as barrier heig
ht, initial rate of gas adsorption, and gas reaction kinetics are investiga
ted. Analysis of steady-state reaction kinetics using I-V method confirmed
that the atomistic hydrogen adsorption process is responsible for the barri
er height change in the diodes. (C) 2001 Elsevier Science B.V. All rights r
eserved.