Surface Passivation of Germanium Using SF<inf>6</inf> Plasma to Reduce Source/Drain Contact Resistance in Germanium n-FET

Gwang Sik Kim, Seung Hwan Kim, Jeong Kyu Kim, Changhwan Shin, Jin Hong Park, Krishna C. Saraswat, Byung Jin Cho, Hyun-Yong Yu

Research output: Contribution to journalArticle

15 Citations (Scopus)


We demonstrate Fermi-level unpinning and contact resistance reduction by surface passivation using SF<inf>6</inf> plasma treatment of a metal/germanium (Ge) contact. A specific contact resistivity (ρ<inf>c</inf>) of 1.14 × 10<sup>-3</sup>~Ω. cm<sup>2</sup> and 0.31 eV of Schottky barrier height is achieved for a Ti/SF<inf>6</inf>-treated n-type Ge (n-Ge) ( N<inf>d</inf>= 1 × 10<sup>17</sup> cm<sup>-3</sup>) contact, exhibiting 1700 times ρ<inf>c</inf> reduction from a Ti/nontreated n-Ge contact. A convenient and effective passivation process of the Ge surface is presented to alleviate Fermi-level pinning at metal/Ge contact and lower source/drain contact resistance of Ge n-type field-effect transistors.

Original languageEnglish
Article number7116476
Pages (from-to)745-747
Number of pages3
JournalIEEE Electron Device Letters
Issue number8
Publication statusPublished - 2015 Aug 1



  • contact resistance
  • Fermi-level unpinning
  • germanium
  • SF6 plasma
  • surface passivation

ASJC Scopus subject areas

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

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