Lattice disorder and N elemental segregation in ion implanted GaN epilayer

• Published in: Applied surface science 2020-01, Vol.499, p.143911, Article 143911
• Main Authors: Li, B.S., Liu, H.P., Xu, L.J., Wang, J., Song, J., Peng, D.P., Li, J.H., Zhao, F.Q., Kang, L., Zhang, T.M., Tang, H.X., Xiong, An.L.
• Format: Article
• Language: English
• Subjects: Dislocation loops; GaN; He implantation; Lattice disorder; Transmission electron microscopy
• ISSN: 0169-4332; 1873-5584
• DOI: 10.1016/j.apsusc.2019.143911

The lattice disorder and elemental distribution in He-implanted GaN epilayer at a fluence of 4 × 1016 He+/cm2 at 450 °C have been investigated by a combination of conventional, high resolution transmission electron microscopy and electron energy loss spectroscopy. High resolution transmission electron microscopy shows interstitial-type dislocation loops attached to He bubbles. The nature of dislocation loops and stacking faults are carefully investigated by high resolution transmission electron microscopy. Electron energy loss spectroscopy shows the deficit of N atoms and enriched Ga nanocrystals formed in the damage region, which is comparable with the previous reports. In addition, the chemical environment of nitrogen upon He+ implantation is first investigated in the present experimental results. The research results will be used for understanding ion irradiation-induced damage in GaN. •Lattice disorder in He+ ion-implanted GaN at 450 °C was investigated.•> The nature of dislocation loops and stacking faults are investigated by transmission electron microscopy.•> Electron energy loss spectroscopy shows the deficit of N atoms and Ga nanocrystals formed in the damage region.