On a new scaling for semiconductor device equations and its asymptotic analysis

The aim of this paper is to present a new scaling which is appropriate for modeling reverse biased semiconductor devices with moderately high applied potential and its asymptotic analysis. This scaling was motivated by the mo deling of oxygen sensors. It is compared to the ones leading to (a) electro neutrality, (b) the existence of a depletion zone. With our scaling such a zone may appear within a boundary layer. A particular attention is paid to the qualitative dependence of the asymptotic solution to the boundary value of the concentration of carrier.