[ThA2] Joint-Novel Nitride Devices/Processes/Materials

11:00 AM - 11:30 AM JST(2:00 AM - 2:30 AM UTC)

[ThA2-01 Invited] Study on Intrinsic Point Defects in GaN Formed by Electron Beam Irradiation

〇Masashiro Horita¹, Jun Suda¹ (1. Nagoya Univ. (Japan))

To examine the relationship between deep levels and intrinsic defects,electron-beam (EB) irradiation was applied to n- and p-type GaN layers grown on freestanding GaN substrates, and traps in these layers were characterized by deep-level transient spectroscopy (DLTS). Two electron trap levels, EE1 (Ec–0.13 eV) and EE2 (Ec–(0.98–1.1 eV)), and one hole trap level, EHa (Ev+0.52 eV), were identified and attributed to N-displacement-related intrinsic point defects. Compared with transition levels predicted by first-principles calculations using a hybrid functional, the most likely assignments are EE1 to V_N(+/0) and EE2 to N_I(0/–). In contrast, EHa may correspond to either V_N (3+/+) or N_I (2+/+). The correlation between trap density and irradiation fluence, along with the annealing behavior of EB-induced traps, supports these assignments. These findings enhance understanding of process-induced point defects in GaN-based devices and provide a foundation for their further identification and control.