Depth profiling of E C – 0.26 eV electron traps introduced in homoepitaxial n-type GaN by ultra-low-dose Si-ion implantation and subsequent annealing

Si ions were implanted into homoepitaxial n-type GaN at a peak concentration of 3 × 10 14 cm −3 with subsequent annealing, and the associated formation of electron traps was investigated in detail using deep-level transient spectroscopy. A major electron trap was identified as 0.26 eV below the conduction band minimum and this trap concentration increased with increasing post-implantation annealing temperature, to a value of 6–8 × 10 15 cm −3 . Significant increases in the net donor concentration ( N D ) were also observed within the implanted region. The profile of the electron trap concentration was correlated with these increases in N D , suggesting that these traps acted as donors.