Author(s) Eadi, S.Babu; Lee, J.Chan; Song, H.S.; Oh, J.; Lee, G.W.; Lee, H.D.
Journal Sci Rep
Date Published 2020 Mar 04

Ultra-low contact resistance at the interface between NiGe and p-Ge, i.e., NiGe/p-Ge was achieved by introducing terbium (Tb) as an interlayer in forming NiGe using Tb/Ni/TiN structure. The contact resistance value obtained using the circular transmission line model for an 8-nm thick Tb interlayer sample was 7.21 × 10 Ω·cm, which is two orders of magnitude less than that of reference sample (without the Tb interlayer) of 7.36 × 10 Ω·cm. The current-voltage characteristics were studied at a temperature range of -110 ~ 25 °C to determine the effective Schottky barrier height (eSBH). An eSBH of 0.016 eV was obtained for the 8-nm thick Tb interlayer. Various Tb interlayer thicknesses were selected to study their effect on the contact resistance. The Tb interlayer surface and structural properties were characterized using FESEM, XRD, XPS, TEM, and SIMS analyses.

DOI 10.1038/s41598-020-61011-4
ISSN 2045-2322
Citation Sci Rep. 2020;10(1):4054.