Tantalum nitride metal gate FD-SOI CMOS FETs using low resistivity self-grown bcc-tantalum layer

Hiroyuki Shimada, Ichiro Ohshima, Takeo Ushiki, Shigetoshi Sugawa, Tadahiro Ohmi

Research output: Contribution to journalArticlepeer-review

25 Citations (Scopus)


A Tantalum Nitride (TaNx) metal gate complementary metal oxide semiconductor (CMOS) technology using low-resistivity (∼ 15 μΩcm), bcc(body-centered-cubic)-phase tantalum metal layer has been developed, featuring low-temperature processing below 550°C except for gate oxide formation. It was found for the first time that TaNx works not only as a buffer layer which prevents tantalum metal film and gate oxide film from reaction with each other, but also as a seed layer which helps self-growth of bcc-phase tantalum films by hetero-epitaxy. Furthermore, we have demonstrated that the work function of TaNx gate is close to midgap of silicon, hence similar to Titanium Nitride (TiNx) gate. We have also demonstrated that MOS capacitors on bulk and fully-depleted silicon-on-insulator(FDSOI) CMOS with TaNx/bcc-Ta/TaNx stacked metal gate structure have excellent electrical characteristics and that the ring-oscillator fabricated using the stacked metal gate CMOS can be operated successfully with 3.8 nm-thickness gate oxide.

Original languageEnglish
Pages (from-to)1619-1626
Number of pages8
JournalIEEE Transactions on Electron Devices
Issue number8
Publication statusPublished - 2001 Aug


  • Barrier height
  • Constant current stress
  • Epitaxial growth
  • Gate injection
  • Metal gate
  • Silicon-on-insulator
  • Tantalum
  • Tantalum nitride
  • Work function
  • Xenon

ASJC Scopus subject areas

  • Electronic, Optical and Magnetic Materials
  • Electrical and Electronic Engineering


Dive into the research topics of 'Tantalum nitride metal gate FD-SOI CMOS FETs using low resistivity self-grown bcc-tantalum layer'. Together they form a unique fingerprint.

Cite this