Data for Combining low-temperature gettering with phosphorus diffusion gettering for improved multicrystalline silicon

Low-temperature gettering applied after standard phosphorus diffusion gettering is found to provide a >40% improvement in minority carrier lifetime in samples from the top and bottom of an ingot. The best results are achieved at 300 °C with very long annealing times (>24 h).

Improvements in the lifetime do not correlate with changes in interstitial iron concentration. Experiments are performed to assess whether the presence of a phosphorus-diffused emitter affects low-temperature gettering, and results from sister samples show the low-temperature gettering behavior is not affected by the existence of an emitter. Further experiments show that low-temperature gettering prior to phosphorus diffusion results in a 20% higher lifetime after phosphorus diffusion.