Title :
Surface Passivation of Germanium Using SF6 Plasma to Reduce Source/Drain Contact Resistance in Germanium n-FET
Author :
Gwang-Sik Kim ; Seung-Hwan Kim ; Jeong-Kyu Kim ; Changhwan Shin ; Jin-Hong Park ; Saraswat, Krishna C. ; Byung Jin Cho ; Hyun-Yong Yu
Author_Institution :
Sch. of Electr. Eng., Korea Univ., Seoul, South Korea
Abstract :
We demonstrate Fermi-level unpinning and contact resistance reduction by surface passivation using SF6 plasma treatment of a metal/germanium (Ge) contact. A specific contact resistivity (Pc) of 1.14 × 10-3 Ω · cm2 and 0.31 eV of Schottky barrier height is achieved for a Ti/SF6-treated n-type Ge (n-Ge) (Nd = 1 × 1017 cm-3) contact, exhibiting 1700 times Pc 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.
Keywords :
Schottky barriers; contact resistance; field effect transistors; germanium; passivation; plasma applications; sulphur compounds; titanium; Fermi-level unpinning; Ge; Schottky barrier height; Ti-SF6; contact resistivity; germanium n-FET; metal-germanium contact; n-type contact; n-type field-effect transistors; passivation process; plasma treatment; source-drain contact resistance; surface passivation; Metals; Passivation; Plasmas; Rough surfaces; Sulfur hexafluoride; Surface roughness; Contact resistance; Fermi-level unpinning; SF6 plasma; contact resistance; germanium; surface passivation;
Journal_Title :
Electron Device Letters, IEEE
DOI :
10.1109/LED.2015.2440434
