The physical and electrical properties of polycrystalline Si1-xGex as a gate electrode material for ULSI CMOS structures

Sung Kwan Kang, Dae Hong Ko, Tae Hang Ahn, Moon Sik Joo, In Seok Yeo, Sung Jin Whoang, Doo Young Yang, Chul Joo Whang, Hoo Jeong Lee

Research output: Contribution to journalArticle


Poly Si1-xGex films have been suggested as a promising alternative to the currently employed poly-Si gate electrode for CMOS technology due to lower resistivity, less boron penetration, and less gate depletion effect than those of poly Si gates. We investigated the formation of poly Si1-xGex films grown by UHV CVD using Si2H6 and GeH4 gases, and studied their microstructures as well as their electrical characteristics. The Ge content of the Si1-xGex films increased linearly with the flux of the GeH4 gas up to x=0.3, and saturated above x=0.45. The deposition rate of the poly Si1-xGex films increased linearly with the flux of the GeH4 gas up to x=0.1, above which it is slightly changed. The resistivity of the Si1-xGex films decreased as the Ge content increased, and was about one half of that of poly-Si films at the Ge content of 45%. The C-V measurements of the MOSCAP structures with poly Si1-xGex gates demonstrated that the flat band voltage of the poly Si1-xGex films was lower than that of poly-Si films by 0.2V.

Original languageEnglish
Pages (from-to)C711-C716
JournalMaterials Research Society Symposium - Proceedings
Publication statusPublished - 2001 Jan 1


All Science Journal Classification (ASJC) codes

  • Materials Science(all)
  • Condensed Matter Physics
  • Mechanics of Materials
  • Mechanical Engineering

Cite this