An observation of charge trapping phenomena in GaN/AlGaN/ Gd₂ O₃ /Ni-Au structure

Charge trapping, especially electron trapping phenomena in GaN/AlGaN/ Gd₂ O₃ /Ni-Au metal-oxide-semiconductor structure have been investigated. Owing to crystallization of Gd₂ O₃ film after annealing at 900 °C in ambient air for 30 s, a significant memory window of 1.6 V is observed under 5 V@100 ms programming pulse compared with that of as-deposited sample. The fabricated structure exhibits no erase phenomena under large negative bias of -20 V. Only time dependent natural charge loss is occurred. Even so, 0.9 V of memory window is still remained after 21 h of retention. Good endurance of 10³ cycles with 2.0 V memory window is also obtained.