The role of fluorine in a BF2 implant has been investigated by implanting BF2, B alone and different combinations of B and F at equivalent implant energies. Each combination was designed to test for something, such as the effect of fluorine after B was implanted or the F damage before B was implanted. The wafers from each group received a spike anneal at 1075°C. The resulting boron profiles after implant and after spike anneal were obtained by SIMS analysis. Sheet resistance was measured and compared with the values calculated from the profiles. The junctions with boron implant had the smallest sheet resistance whereas those obtained with boron implant following F implant had the largest sheet resistance. The SIMS profiles supported these results. The profiles do suggest that the presence of fluorine reduced the transient enhanced diffusion of boron.
"The Effect of Fluorine on Boron Diffusion,"
Journal of the Microelectronic Engineering Conference: Vol. 10
, Article 13.
Available at: http://scholarworks.rit.edu/ritamec/vol10/iss1/13