Effect of Pre- and Post-Epitaxial Annealing on Oxygen Precipitation and Internal Gettering in N/N+(100) Epitaxial Wafers

Abstract

Oxygen precipitation in silicon heavily-doped with antimony, particularly at the concentration range higher than 7×1017 atoms/cm3, is known to be severely suppressed because of the doping concentration effect. This results in a reduction in internal gettering (IG) efficiency in the N/N+ epitaxial wafers. In this work, substrate wafers heavily-doped with antimony were pre-annealed prior to the epitaxial deposition process. Post-epitaxial annealing was used for enhancing precipitation in asdeposited epitaxial wafers. The results indicate that both pre- and post-epitaxial annealing can improve oxygen precipitation and IG efficiency. The relationship between oxide breakdown, generation lifetime and bulk defect density is observed.