Method for suppressing transient enhanced diffusion of dopants in silicon

摘要

Method for suppressing the transient enhanced diffusion (TED) of a dopant implanted in a thin surface layer of a semiconductor substrate, the TED being normally caused by the interaction between the dopant and the lattice damage caused by the implantation of the dopant itself or by pre-amorphization implantations during the post-implantation annealing thermal process. The aforesaid heat treatment is carried out on a crystalline semiconductor having an amorphous surface layer in which the dopant is implanted and having a layer rich in a trap element which effectively traps self-interstitial point defects. The layer rich in a trap element is spatially separated from the dopant-rich surface layer and is interposed between the dopant-rich surface layer and the interface between the amorphous and crystalline regions of the substrate.