Effects of Illumination on Ar+-Implanted n-Type 6H-SiC Epitaxial Layers

Abstract

Argon ions were implanted into n-type 6H-SiC epitaxial layers at 600°C. Postimplantation annealing was carried out at 1,600°C for 5 min in an Ar ambient. Four implantation-induced defect levels were observed at E C -0.28 eV, E C -0.34 eV, E C -0.46 eV, and E C -0.62 eV by deep level transient spectroscopy. The defect center at E C -0.28 eV is correlated with ED 1 /ED 2 and with ID 5 . The defect at E C -0.46 eV with a capture cross section of 7.8 · 10 )16 cm 2 is correlated with E1/E2, while the defect at E C -0.62 eV with a capture cross section of 2.6 · 10 )14 cm 2 is correlated with Z1/Z2. Photo deep level transient spectroscopy was also used to study these defects. Upon illumination, the amplitudes of the deep level transient spectroscopy (DLTS) peaks increased considerably. Two emission components of Z1/Z2 were revealed: one fast and the other slow. The fast component could only be observed with a narrow rate window. In addition, a new defect was observed on the low-temperature side of the defect at E C -0.28 eV when the sample was illuminated.