The effect of post-deposition H2 annealing (PDHA) on the reduction of a contact resistance by the metal-interlayer-semiconductor (M-I-S) source/drain (S/D) structure of the germanium (Ge) n-channel field-effect transistor (FET) is demonstrated in this letter. The M-I-S structure reduces the contact resistance of the metal/n-type Ge (n-Ge) contact by alleviating the Fermi-level pinning (FLP). In addition, the PDHA induces interlayer doping and interface controlling effects that result in a reduction of the tunneling resistance and the series resistance regarding the interlayer and an alleviation of the FLP, respectively. A specific contact resistivity ( ρc) of 3.4 × 10-4 Ω · cm2 was achieved on a moderately doped n-Ge substrate (1 × 1017 cm -3) , whereby 5900× reduction was exhibited from the Ti/n-Ge structure, and a 10× reduction was achieved from the Ti/Ar plasma-treated TiO2-x/n-Ge structure. The PDHA technique is, therefore, presented as a promising S/D contact technique for the development of the Ge n-channel FET, as it can further lower the contact resistance of the M-I-S structure.
Bibliographical noteFunding Information:
This work was supported in part by the National Research Foundation of Korea within the Ministry of Science, ICT, and Future Planning through the Basic Science Research Program under Grant 2014R1A1A1036090 and in part by the Technology Innovation Program entitled Technology Development of Ge nMOS/pMOS FinFET for 10nm Technology Node within the Ministry of Trade, Industry & Energy, Korea, under Grant 10048594. The review of this letter was arranged by Editor K. J. Kuhn.
© 1980-2012 IEEE.
- Contact resistance
- Fermi-level unpinning
- post-deposition hydrogen annealing
- titanium dioxide
ASJC Scopus subject areas
- Electronic, Optical and Magnetic Materials
- Electrical and Electronic Engineering