Ion implantation induced nitrogen defects in GaN

Abstract

Ion implantation induced defects in GaN are investigated by using ion beam analysis and scanning spreading resistance microscopy (SSRM) techniques. Different GaN samples were implanted with 300 keV argon (Ar) and 200 keV hydrogen (H) ions, respectively. The samples were characterized with ion beam techniques in channeling mode: Rutherford backscattering (RBS) for Ga defects and nuclear reaction analysis (NRA) for N defects by utilizing the nitrogen resonance reaction 14N(α,α)14N at 3690 keV, to see the individual sublattice damage of Ga and N in GaN. The results show that the relative defect concentration of nitrogen defects are considerably higher than Ga defects at an Ar fluence of 2 × 1015 cm−2. The H+-implanted samples are used to study the influence of the ion-induced damage on the electrical behavior and for depth profiling by using SSRM. The SSRM shows generally a higher resistance in the material for higher fluence, but an inverse fluence dependence on the resistivity is also revealed in the region of the projected range.