The 68th JSAP Spring Meeting 2021

Presentation information

Oral presentation

21 Joint Session K "Wide bandgap oxide semiconductor materials and devices" » 21.1 Joint Session K "Wide bandgap oxide semiconductor materials and devices"

[19a-Z33-1~12] 21.1 Joint Session K "Wide bandgap oxide semiconductor materials and devices"

Fri. Mar 19, 2021 9:00 AM - 12:15 PM Z33 (Z33)

Kazuyuki Uno(Wakayama Univ.), Oshima Yuichi(NIMS)

10:15 AM - 10:30 AM

[19a-Z33-6] Post-deposition annealing effect on ALD-Al2O3 formed on (001) β-Ga2O3

Atsushi Hiraiwa1,4, Kiyotaka Horikawa2, Hiroshi Kawarada1,2,3, Motohisa Kado5, Katsunori Danno5 (1.RONLI, Waseda Univ., 2.FSE, Waseda Univ., 3.KMLMST, Waseda Univ., 4.IMaSS, Nagoya Univ., 5.Toyota Motor Corp.)

Keywords:Al2O3, atomic layer deposition, annealing

Post-deposition annealing (PDA) of atomic-layer-deposited (ALD) Al2O3 films formed on (001) β-Ga2O3 exacerbates the bias instability (BI) of the ALD-Al2O3/(001) β-Ga2O3 capacitors, in a non-monotonic way with PDA temperature. This result makes a stark contrast with that from capacitors that are similarly formed on GaN substrates, where BI was reduced monotonously with PDA temperature. Similar to the GaN capacitors, the leakage current in the (001) β-Ga2O3 capacitors was reduced sharply by the crystallization of the ALD-Al2O3 film, but the threshold temperature for the current reduction was approximately 100ºC lower than that for the GaN capacitors. A space-charge-controlled field emission analysis revealed that this current reduction was mostly caused by the increase in the barrier height against the electron emission from the substrate.