Semiconductor OneSource: Semiconductor Glossary -- Search For : abrupt junction,

Term (Index)	Definition
abrupt junction,	a p-n junction in which dopant concentration changes from one region to the junction to another; difficult to accomplish using conventional doping by diffusion.
diffusion	in general, motion of species in solids in the direction of concentration gradient; (i)diffusion of free charge carriers in semiconductor; (ii) diffusion of dopant atoms in semiconductor at elevated temperature; (iii) diffusion - common name of the high temperature process during which dopant atoms are introduced into semiconductor by diffusion.
graded junction	composition of the layer located at the junction between two materials featuring different lattice constants is gradually modified to accomodate this changes; also a p-n junction in which dopant concentrataion is gradually varied from one region to another.