The codiffusion of arsenic and phosphorus implanted in silicon has bee
n investigated after annealing at 900 and 1000-degrees-C for different
concentrations of the dopants. Analysis of the profiles was performed
using secondary-ion-mass spectroscopy, junction staining, and increme
ntal resistivity and Hall measurements. The results do not evidence an
y direct, interaction between the dopants. All the observed anomalous
effects of the codiffusion, compared with the diffusion of the single
elements by themselves, seem to be justifiable on the basis of the int
eractions between the dopants and the defects produced by ion implanta
tion. In addition, it has been observed that the presence of a high co
ncentration of As atoms makes the annealing of the implantation damage
faster and strongly reduces the P transient-enhanced diffusion. This
effect favors the fabrication of graded shallow junctions with a high-
surface-carrier concentration.