Annealing effects on structural, optical and electrical properties of Al implanted 4H-SiC

Effects of Al ions implantation into n-type 4H-SiC followed by annealing at various temperatures have been studied by Atomic Force Microscopy (AFM), Raman scattering, Fourier transform infrared (FTIR) reflectance spectroscopy, and Hall effect measurements. AFM experiments observed a large amount of discontinuous strips on 4H-SiC surface running along three directions after high temperature annealing. Raman scattering and FTIR spectra jointly indicated the damage and amorphization of 4H-SiC due to Al implantation and the crystal restoration after high temperature annealing. Hall effect measurements revealed that the sample annealed at 1600°C achieved a higher activity ratio and a lower resistivity, which satisfied the application of numerous SiC-based devices.