Effect of carbon codoping on boron diffusion in amorphous silicon

The effect of carbon codoping on boron diffusion in amorphous silicon is investigated during low temperature annealing. The diffusivity of boron is unaffected by carbon codoping, but the fraction of mobile boron is observed to increase with increasing carbon concentration. A concomitant reduction in boron clustering is also observed at higher carbon coimplant concentrations, consistent with a change in the local trap concentration. This is consistent with carbon possibly acting as a trap site for boron and thereby changing the size and dynamics of the boron cluster formation.