Ion Implantation and 1 MeV Electron Irradiation of 4H-SiC—Comparison Studies

摘要

Argon ions (Ar~+) were implanted into n-type 4H-SiC epitaxial layers at 600 ℃. The energy of the ions was 160 keV and at a dose of 2 x 10~(16) cm~(-2). After post-implantation annealing at 1600 ℃, Schottky diodes were fabricated on the ion implanted samples. Bulk n-type 4H-SiC samples were irradiated at room temperature with 1 MeV electrons at doses of 1 x 10~(16) to 5.1 x 10~(17) el/cm~2. The current density of the beam was 0.91 μA/cm~2. Deep Level Transient Spectroscopy (DLTS) was used to characterize the induced defects. DLTS studies of Ar~+ implanted samples showed six defect levels at E_C - 0.18 eV, E_C - 0.23eV, E_C - 0.31eV, E_C - 0.38 eV, E_C - 0.72 eV, and E_C - 0.81 eV. Z1/Z2 defect is the dominant defect in the electron irradiated sample and anneals out completely after 10 minutes at 1000 ℃. However, Z1/Z2 defect in Ar~+ implanted samples was stable up to 1600℃. It is suggested that the annealing behavior of Z1/Z2 depends on the source of its formation.