Barrier height reduction to 0.15eV and contact resistivity reduction to 9.1×10−9 Ω-cm2 using ultrathin TiO2−x interlayer between metal and silicon

Metal-insulator-Si (MIS) tunnel contact is studied using ultrathin, non-stoichiometric TiO
2−x
interlayer on n- and n+ Si. Systematic analysis indicates a record low Schottky barrier height (SBH) of 0.15eV for Ti metal using 10A thick TiO
2−x
interlayer (T
Ins
). Ti/TiO
2−x
/n+ Si contact achieves a record low specific contact resistivity (ρ
c
) of 9.1×10
⁻⁹
Ω-cm
²
.The modeling of ρ
c
suggests tunneling mass, m*
Tunnel
, of 0.7m
0
for TiO
2−x
compared to stoichiometric TiO
2
indicating transition from an insulator to a wide gap semiconductor.