Effective work function modulation of TaN metal gate on Hf O2 after postmetallization annealing

Youhei Sugimoto, Masanari Kajiwara, Keisuke Yamamoto, Yuusaku Suehiro, Dong Wang, Hiroshi Nakashima

Research output: Contribution to journalArticle

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Abstract

The effective work function (m,eff) of TaN on Hf O2 after postmetallization annealing (PMA) was investigated using TaNHf O2 Si O2 Si as a sample structure. We found that m,eff on Hf O2 is stable at PMA temperatures of less than 600 °C and is 4.6 eV, which is approximately 0.2 eV higher than that on Si O2. In contrast, m,eff is modulated by PMA at temperatures greater than 750 °C. An analysis by x-ray photoelectron spectroscopy suggests that the increased m,eff is strongly related to Ta oxide formation near the TaNHf O2 interface. The modulation of m,eff on Hf O2 is discussed on the basis of intrinsic and extrinsic Fermi level pinning due to Ta-O bond formation at the TaNHf O2 interface.

Original languageEnglish
Article number112105
JournalApplied Physics Letters
Volume91
Issue number11
DOIs
Publication statusPublished - Sep 21 2007

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modulation
annealing
metals
x ray spectroscopy
photoelectron spectroscopy
temperature
oxides

All Science Journal Classification (ASJC) codes

  • Physics and Astronomy (miscellaneous)

Cite this

Effective work function modulation of TaN metal gate on Hf O2 after postmetallization annealing. / Sugimoto, Youhei; Kajiwara, Masanari; Yamamoto, Keisuke; Suehiro, Yuusaku; Wang, Dong; Nakashima, Hiroshi.

In: Applied Physics Letters, Vol. 91, No. 11, 112105, 21.09.2007.

Research output: Contribution to journalArticle

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AU - Sugimoto, Youhei

AU - Kajiwara, Masanari

AU - Yamamoto, Keisuke

AU - Suehiro, Yuusaku

AU - Wang, Dong

AU - Nakashima, Hiroshi

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