[13a-B401-1~10] 13.7 Compound and power electron devices and process technology

[13a-B401-1] Bias stability improvement of ALD-Al₂O₃/GaN capacitors by post-deposition annealing

Kiyotaka Horikawa¹, Hiroshi Kawarada^1,2,3, 〇Atsushi Hiraiwa^2,4 (1.FSE, Waseda Univ., 2.RONLI, Waseda Univ., 3.KMLMST, Waseda Univ., 4.IMaSS, Nagoya Univ.)

Keywords:bias stability, Al2O3, post-deposition annealing

The bias stability of atomic-layer-deposited (ALD) Al₂O₃/GaN capacitors is enhanced, without forming blisters (microscopic peeling of thin films), by increasing the ALD temperature to 450 ºC and subsequently annealing the Al₂O₃ film at high temperatures. However, the annealing at 800 ºC and higher crystallizes the Al₂O₃ film and reduces the breakdown lifetime of the capacitors. Therefore, the highest reliability of the ALD-Al₂O₃/GaN capacitors is achieved by forming the Al₂O₃ film at 450 ºC and subsequently annealing the film at 700 ºC.