In situ electrical characteristics and defect dynamics induced by swift heavy ion irradiation in Pt/PtOₓ/β-Ga₂O₃vertical Schottky barrier diodes

• Main Authors: Manikanthababu, N., Sheoran, Hardhyan, Prajna, K., Khan, S. A., Asokan, K., Vas, Joseph Vimal, Medwal, R., Panigrahi, B. K., Singh, R.
• Other Authors: School of Materials Science and Engineering
• Format: Article
• Language: English
• Published: 2022
• Subjects: Science::Physics; Ions; Radiation Effects
• Online Access: https://hdl.handle.net/10356/163770
• Institution: Nanyang Technological University

In situ I – V and C – V measurements were performed on Pt/PtOx/ β -Ga2O3 vertical Schottky barrier diodes (SBD) during 120 MeV Au9+ swift heavy ion (SHI) irradiation in a fluence range of 1×1010 – 2×1012 ions/cm2. The reverse leakage current density increased from 1.21×10−10 to 1.69×10−4 A/cm2 at −1 V. The Schottky barrier height (SBH) remains close to ~1.8 eV up to the fluence of 5×1011 ions/cm2, and however, at the fluences of 1×1012 and 2×1012 ions/cm2, the SBH increased to 1.93 and 2.03 eV, respectively. Also, the ideality factor (IF) increased from 1.07 to 1.38. The in situ C – V measurements showed a similar trend, as the SBH decreased from 2.04 to ~1.88 eV until 5×1011 ions/cm2, but it increased to 2.14 and 2.56 eV at 1×1012 and 2×1012 ions/cm2, respectively. In addition, the doping concentration decreased from 1.01×1016 to 0.27×1016 cm −3 as the defects increased significantly at the fluence of 2×1012 ions/cm2. The cathodoluminescence measurements revealed various Ga and O defects produced during SHI irradiation. Cross-sectional transmission electron microscopy measurements confirmed the formation of tracks within β -Ga2O3 along the SHI path, and these results are explained with the inelastic thermal spike model.