Formation of 0.1 µm N+/P and P+/N junctions by doped silicide technology

A new technique to form very shallow, low resistance, and high surface concentration junctions by diffusing the dopant from doped WSi
2
into the silicon has been developed. The junctions were formed by ion implanting WSi
2
films with As
⁺
, P
⁺
or B
⁺
which then acted as the diffusion sources. Subsequent high temperature processing simultaneously forms the junctions and ohmic contacts to the diffusion areas. N
⁺
/P and P
⁺
/N diodes with very shallow juctions have been formed by this doped silicide technology. Dopant diffusion in the WSi
2
and redistribution behavior in the SiO
2
/WSi
2
/Si structure with a wide range of implant doses, anneal temperatures and times have been characterized.