Impact of Al-Ion Implantation on the Formation of Deep Defects in n-Type 4H-SiC

In this work, deep defects in an aluminum-implanted 4H-SiC n-type epitaxy are discussed in dependence on following influencing factors: concentration of implanted aluminum, implantation energy, implantation at 500°C and at room temperature, as well as ascending or descending order of implantation energies during ion implantation using Gaussian profiles. The compensation ratio, which reaches values up to 90% of the implanted aluminum concentration, is determined by Hall Effect measurements. Compensating defect centers (Z 1/2 -, ON x -defects) are detected by Deep Level Transient Spectroscopy after high energy ion implantation using an energy filter, followed by an annealing and an oxidation process.