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

Heavily doped p-type layers obtained by implanting aluminum near its solubility limit (similar to2x10(20) Al/cm(3)) in 4H-SiC are characterized as a function of the implant and anneal temperatures. For a typical implant temperature of 650degreesC, Al activation rates of similar to6%-35% are obtained for anneals from 1600 to 1750degreesC, respectively. For higher temperature implants at 1000degreesC, the Al activation rates are significantly improved, approaching similar to100% for the same anneal temperatures, with a best p-type resistivity of similar to0.20 Omega 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. (C) 2004 American Institute of Physics.