Hafnium silicate gate dielectrics in GaN metal oxide semiconductor capacitors

Toshihide Nabatame, Erika Maeda, Mari Inoue, Kazuya Yuge, Masafumi Hirose, Koji Shiozaki, Naoki Ikeda, Tomoji Ohishi, Akihiko Ohi

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Characteristics of hafnium silicate as gate dielectric in n-GaN capacitors were investigated. The Hf0.57Si0.43O x , Hf0.64Si0.36O x and HfO2 films exhibited high dielectric constants of 15.4, 15.9, and 17.6, respectively. The Hf0.57Si0.43O x and Hf0.64Si0.36O x films, which had an amorphous structure, showed superior properties, including a minimal flatband voltage (V fb) hysteresis (≤70 mV) and a small V fb shift (≤-0.45 V), as well as a low interface state density (∼4 × 1011 cm-2 eV-1 at -0.4 eV from conduction band), and a high breakdown electric field (≥8.6 MV cm-1) compared to those of a polycrystalline HfO2 film.

Original languageEnglish
Article number011009
JournalApplied Physics Express
Issue number1
Publication statusPublished - 2019 Jan 1


ASJC Scopus subject areas

  • Engineering(all)
  • Physics and Astronomy(all)

Cite this

Nabatame, T., Maeda, E., Inoue, M., Yuge, K., Hirose, M., Shiozaki, K., ... Ohi, A. (2019). Hafnium silicate gate dielectrics in GaN metal oxide semiconductor capacitors. Applied Physics Express, 12(1), [011009]. https://doi.org/10.7567/1882-0786/aaf62a