Resistance Changes in Silicon by MeV Proton Implantation

Protons were implanted into the phosphorus‐doped epitaxial region of insulated gate transistors at MeV energies and doses in the range of those used for lifetime control in silicon power devices. Spreading resistance depth profiles were used to study changes in resistance after implantation and subsequent annealing. After implantation, the largest resistance increase occurs near the proton range; the resistance profile is similar to the expected displaced atom profile. The resistance increase is attributed to carrier compensation rather than to a decreased mobility. At a dose of 10 13 cm −2 1.5 MeV protons, the resistance increase is observed to saturate. The annealing behavior of the resistance changes is complex: there is evidence for reverse annealing and resistance decreases (donor action) at 350°C. Annealing of the resistance changes produced at the highest dose is incomplete after 30 min at 520°C.