An analytical model for high-concentration diffusion profiles was previously developed, where the diffusion coefficients depend on the concentration of impurities. By conducting experiments, we have obtained data on the diffusion of low-energy ion-implanted B, As, and BF2 over a wide temperature range. It is possible to describe the diffusion profiles using a constant surface concentration source with an offset period related to the transient enhanced diffusion. The surface concentration, N-s, was dependent on the temperature for B but was less dependent for that of As. N-s was lower in samples implanted with BF2+ than with B+. Therefore, the sheet resistance of BF2+ ion-implanted layers will always be lower than that of B+ implanted layers for a given junction depth. The offset time is independent of the impurities, and depends on temperature.