The Interaction Of The Surface With The Bulk In A Semiconductor

When we speak of the interaction of the surface of a crystal with its bulk, we mean the correlation between the properties of the bulk and surface. A number of surface properties, such as the chemisorptivity of the surface, the charge of the surface, and the reactivity of the chemisorbed partic1es, are determined, as we have seen, by the position of the Fermi level at the crystal surface. Here we will characterize the position of the Fermi level by the distance between the level and the bottom of the conduction band and denote this distance by ∈_s. On the other hand, a number of bulk properties, such as the electrical conductivity of the crystal and the carrier recombination rate, are determined by the position of the Fermi level in the bulk, which we characterize by ∈_v, where ∈_v is the distance between the Fermi level and the bottom of the conduction band in the bulk of the crystal. There is a unique relationship between ∈_s and ∈_v