Approximate analytical solutions of diffusional boundary-value problems by the method of finite zone continuity

An approximate technique for solving diffusional boundary-value problems is described which has considerable generality and yields analytical results. The main feature of the method involves the relaxation of the pointwise requirement of material conservation while insisting that conservation is established at the boundaries of a finite region of the diffusion field. The main effect of this approach is to allow one to deal with the diffusion equation as though it were an ordinary rather than a partial differential equation. Several applications are discussed, and, in particular, one which has relevance with respect to the following paper on stacking-fault generation in silicon.