The diffusion analysis of implanted heavy metals in 4H-SiC

We studied the behavior of several heavy metals implanted into 4H-SiC during high-temperature annealing. We evaluated the diffusion of Iron, Nickel, and Titanium in 4H-SiC after Al^+ and Ge^+ implantation in detail. The diffusion of these metals depends on the existence of ion species in 4H-SiC and implantation damage. Furthermore, implantation temperature of Al^+ and Ge^+ that has a large impact on defects generation plays an important role for the diffusion of heavy metals in 4H-SiC. It should be noted that the implantation damages such as vacancy and interstitial atom enhance the diffusion of heavy metals in 4H-SiC. The diffusion coefficient in SiC becomes larger in the order of Ti, Fe, and Ni. It is found that this order does not change depending on the implanted ion species and implantation temperature, although the diffusion coefficient significantly changes. Graphical abstract