Effect of implantation damage on transient loss of phosphorus in silicon

• Capacity of phosphorus segregation at interface remains intact with implantation.
• Damage provides driving force of phosphorus uphill diffusion toward surface.
• Uphill diffusion enhances phosphorus loss when most interface traps are empty.

In this study, samples were cycled between silicon implantation and rapid thermal annealing to understand the impact of implantation damage on the phosphorus dose loss due to interface segregation. The total trap density for interface segregation was not affected by implantation damage because silicon implantation did not change the maximum dose loss in samples initially implanted by phosphorus at a high fluence of 2 × 1015 cm−2. However, the shape of phosphorus diffusion profiles was changed with silicon implantation, implying that the implantation damage promoted the diffusion of phosphorus toward surface. The promotion of the diffusion toward surface increased the dose loss in samples with a low initial phosphorus fluence of 7 × 1013 cm−2 because most of the segregation sites at the interface were empty.