The influence of postgrowth high-temperature anneals between 1400°C and 2400°C on the behavior of the D 1 center in semi-insulating 4H-SiC was studied by photoluminescence. The optical signature of D 1 was observed up to 2400°C with intensity maxima at 1700°C and 2200°C. It was also found that changes in the postannealing cooling rate drastically influence the behavior of the D 1 center and the concentrations of the V C, V Si, V C-V Si, and V C-C Si lattice defects observed from electron paramagnetic resonance experiments. The change in intensity of the D 1 defect has some correlation with the intensity change of the V C-V Si pair defect at temperatures above 1900°C. In addition, infrared photoluminescence spectroscopy studies showed that changes in the intensity of the D 1 defect at 2100°C to 2400°C annealing temperatures and variable cool-down rates have close correlation with intensity changes of the UD2 defect.
All Science Journal Classification (ASJC) codes
- Electronic, Optical and Magnetic Materials
- Condensed Matter Physics
- Electrical and Electronic Engineering
- Materials Chemistry