High temperature high-dose implantation of aluminum in 4H-SiC

摘要

Heavily doped p-type layers obtained by implanting aluminum near its solubility limit (～2×10~(20) Al/cm~(3)) in 4H-SiC are characterized as a function of the implant and anneal temperatures. For a typical implant temperature of 650℃, Al activation rates of ～6%-35% are obtained for anneals from 1600 to 1750℃, respectively. For higher temperature implants at 1000℃, the Al activation rates are significantly improved, approaching ～100% for the same anneal temperatures, with a best p-type resistivity of ～0.20 Ω cm. For SiC device fabrication, these results demonstrate that by using higher Al implant temperatures, lower anneal temperatures can be used while obtaining close to 100% Al activation.