Explicit formulation for the response of neat oxide semiconductor gas sensor to reducing gas

The response of a neat semiconductor gas sensor to a reducing gas has successfully been formulated theoretically as a function of the partial pressure of target gas under the conditions of volume depletion and the presence of residual electrons inside the depletion region. This was achieved by considering the steady state of resistance instead of that of the surface density of adsorbed oxide ions. The derived equation, given as a combination of several physicochemical parameters, reproduces main features of practical response behavior well. It is exemplified that the equation provides the analysis or extension of response data with an important theoretical base.