Comprehensive study and design of scaled metal/high-k/Ge gate stacks with ultrathin aluminum oxide interlayers

Asahara, Ryohei; Hideshima, Iori; Oka, Hiroshi; Minoura, Yuya; Hosoi, Takuji; Shimura, Takayoshi; Watanabe, Heiji; Ogawa, Shingo; Yoshigoe, Akitaka; Teraoka, Yuden

doi:10.1063/1.4922447

Title: Comprehensive study and design of scaled metal/high-k/Ge gate stacks with ultrathin aluminum oxide interlayers

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Abstract

Advanced metal/high-k/Ge gate stacks with a sub-nm equivalent oxide thickness (EOT) and improved interface properties were demonstrated by controlling interface reactions using ultrathin aluminum oxide (AlO{sub x}) interlayers. A step-by-step in situ procedure by deposition of AlO{sub x} and hafnium oxide (HfO{sub x}) layers on Ge and subsequent plasma oxidation was conducted to fabricate Pt/HfO{sub 2}/AlO{sub x}/GeO{sub x}/Ge stacked structures. Comprehensive study by means of physical and electrical characterizations revealed distinct impacts of AlO{sub x} interlayers, plasma oxidation, and metal electrodes serving as capping layers on EOT scaling, improved interface quality, and thermal stability of the stacks. Aggressive EOT scaling down to 0.56 nm and very low interface state density of 2.4 × 10{sup 11 }cm{sup −2}eV{sup −1} with a sub-nm EOT and sufficient thermal stability were achieved by systematic process optimization.

Authors:

Asahara, Ryohei; Hideshima, Iori; Oka, Hiroshi; Minoura, Yuya; Hosoi, Takuji; Shimura, Takayoshi; Watanabe, Heiji ^[1]; Ogawa, Shingo ^[1]; Yoshigoe, Akitaka; Teraoka, Yuden ^[2]

Graduate School of Engineering, Osaka University, 2-1 Yamadaoka, Suita, Osaka 565-0871 (Japan)
Japan Atomic Energy Agency, 1-1-1 Kouto, Sayo-cho, Sayo-gun, Hyogo 679-5148 (Japan)

Publication Date:: Mon Jun 08 00:00:00 EDT 2015

OSTI Identifier:: 22412570

Resource Type:: Journal Article

Journal Name:: Applied Physics Letters

Additional Journal Information:: Journal Volume: 106; Journal Issue: 23; Other Information: (c) 2015 AIP Publishing LLC; Country of input: International Atomic Energy Agency (IAEA); Journal ID: ISSN 0003-6951

Country of Publication:: United States

Language:: English

Subject:: 37 INORGANIC, ORGANIC, PHYSICAL AND ANALYTICAL CHEMISTRY; 71 CLASSICAL AND QUANTUM MECHANICS, GENERAL PHYSICS; ALUMINIUM OXIDES; ELECTRODES; GERMANIUM; GERMANIUM OXIDES; HAFNIUM OXIDES; LAYERS; PLATINUM

Citation Formats


                    Asahara, Ryohei, Hideshima, Iori, Oka, Hiroshi, Minoura, Yuya, Hosoi, Takuji, Shimura, Takayoshi, Watanabe, Heiji, Ogawa, Shingo, Toray Research Center Inc., 3-3-7 Sonoyama, Otsu, Shiga 520-8567, Yoshigoe, Akitaka, and Teraoka, Yuden. Comprehensive study and design of scaled metal/high-k/Ge gate stacks with ultrathin aluminum oxide interlayers.  United States: N. p., 2015. 
        Web.  doi:10.1063/1.4922447.

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                    Asahara, Ryohei, Hideshima, Iori, Oka, Hiroshi, Minoura, Yuya, Hosoi, Takuji, Shimura, Takayoshi, Watanabe, Heiji, Ogawa, Shingo, Toray Research Center Inc., 3-3-7 Sonoyama, Otsu, Shiga 520-8567, Yoshigoe, Akitaka, & Teraoka, Yuden. Comprehensive study and design of scaled metal/high-k/Ge gate stacks with ultrathin aluminum oxide interlayers.  United States.  https://doi.org/10.1063/1.4922447

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                    Asahara, Ryohei, Hideshima, Iori, Oka, Hiroshi, Minoura, Yuya, Hosoi, Takuji, Shimura, Takayoshi, Watanabe, Heiji, Ogawa, Shingo, Toray Research Center Inc., 3-3-7 Sonoyama, Otsu, Shiga 520-8567, Yoshigoe, Akitaka, and Teraoka, Yuden. 2015.  
        "Comprehensive study and design of scaled metal/high-k/Ge gate stacks with ultrathin aluminum oxide interlayers".  United States.  https://doi.org/10.1063/1.4922447.

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@article{osti_22412570,

  title        = {Comprehensive study and design of scaled metal/high-k/Ge gate stacks with ultrathin aluminum oxide interlayers},

  author       = {Asahara, Ryohei and Hideshima, Iori and Oka, Hiroshi and Minoura, Yuya and Hosoi, Takuji and Shimura, Takayoshi and Watanabe, Heiji and Ogawa, Shingo and Toray Research Center Inc., 3-3-7 Sonoyama, Otsu, Shiga 520-8567 and Yoshigoe, Akitaka and Teraoka, Yuden},

  abstractNote = {Advanced metal/high-k/Ge gate stacks with a sub-nm equivalent oxide thickness (EOT) and improved interface properties were demonstrated by controlling interface reactions using ultrathin aluminum oxide (AlO{sub x}) interlayers. A step-by-step in situ procedure by deposition of AlO{sub x} and hafnium oxide (HfO{sub x}) layers on Ge and subsequent plasma oxidation was conducted to fabricate Pt/HfO{sub 2}/AlO{sub x}/GeO{sub x}/Ge stacked structures. Comprehensive study by means of physical and electrical characterizations revealed distinct impacts of AlO{sub x} interlayers, plasma oxidation, and metal electrodes serving as capping layers on EOT scaling, improved interface quality, and thermal stability of the stacks. Aggressive EOT scaling down to 0.56 nm and very low interface state density of 2.4 × 10{sup 11 }cm{sup −2}eV{sup −1} with a sub-nm EOT and sufficient thermal stability were achieved by systematic process optimization.},

  doi          = {10.1063/1.4922447},

  url          = {https://www.osti.gov/biblio/22412570},
  journal      = {Applied Physics Letters},

  issn         = {0003-6951},

  number       = 23,

  volume       = 106,

  place        = {United States},

  year         = {Mon Jun 08 00:00:00 EDT 2015},

  month        = {Mon Jun 08 00:00:00 EDT 2015}

}

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