IBIL Measurement and Optical Simulation of the D_I Center in 4H-SiC

In this paper, D_I defects are studied via experiments and calculations. The 2 MeV H⁺ is used to carry on an ion-beam-induced luminescence (IBIL) experiment to measure the in-situ luminescence of untreated and annealed 4H-SiC at 100 K. The results show that the luminescence intensity decreases rapidly with increasing H⁺ fluence, which means the losses of optical defect centers. In addition, the evident peak at 597 nm (2.07 eV) is the characteristic peak of 4H-SiC, and the weak peak between 400 nm and 450 nm is attributed to the D_I optical center. Moreover, the first-principles calculation of 4H-SiC is adopted to discuss the origin of D_I defects. The optical transition of the defect Si_C(C_Si)₂ from q = 0 to q = 1 is considered the experimental value of the D_I defect center.