Reduced diffusion of a mobile specie from a metal oxide ceramic into the substrate

摘要

A scavenger layer is provided to prevent the diffusion of an excess mobile specie from a metal oxide ceramic into unwanted parts of a device. The scavenger layer is provided above the metal oxide ceramic. As the excess mobile specie diffuses out of the metal oxide ceramic, it migrates toward the scavenger layer and reacts with it. The reaction consumes the excess mobile specie.