Moisture-absorption-free LaTaON as gate dielectric of Ge MOS devices

Lu Liu, Zhi Xiang Cheng, Jing Ping Xu, Yong Huang, Pui To Lai, Wing Man Tang

Research output: Journal article publicationJournal articleAcademic researchpeer-review

1 Citation (Scopus)


In order to improve the hygroscopic property of LaON and also maintain its excellent interface quality with Ge, LaON incorporated with Ta is proposed and its hygroscopic and electrical properties are investigated by using dry and wet annealing. It is found that large improvement in hygroscopic property can be obtained by the Ta incorporation, and also the LaTaON film exhibits excellent interface quality with the Ge substrate due to the capability of TaON in blocking elemental inter-diffusions and also the passivation effect of LaGeO x N y formed at the LaTaON/Ge interface. Therefore, LaTaON can be considered as a high-quality gate dielectric in Ge MOS device to achieve excellent interfacial and electrical properties, e.g. in this work: high k value (21.0), low interface-state density (5.94 × 10 11 cm −2 eV −1 ), low gate leakage current (3.07 × 10 −4 A/cm 2 at V g = V fb + 1 V) and high resistance against moisture absorption.

Original languageEnglish
Pages (from-to)462-466
Number of pages5
JournalApplied Surface Science
Publication statusPublished - 15 Feb 2019


  • Ge MOS
  • Hygroscopic property
  • Interface quality
  • LaTaON dielectric

ASJC Scopus subject areas

  • Chemistry(all)
  • Condensed Matter Physics
  • Physics and Astronomy(all)
  • Surfaces and Interfaces
  • Surfaces, Coatings and Films

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