  Contact resistance and thermal degradation of metal-silicon contacts are
challenges in nanoscale CMOS as well as in power device applications. Titanium
silicide (TiSi) contacts are commonly used metal-silicon contacts, but are
known to diffuse into the active region under high current stress. In this
paper we show that a graphenic carbon (C) contact deposited on n-type silicon
(C-Si) by CVD, has the same low Schottky barrier height of 0.45 eV as TiSi, but
a much improved reliability against high current stress. The C-Si contact is
over 100 million times more stable against high current stress pulses than the
conventionally used TiSi junction. The C-Si contact properties even show
promise to establish an ultra-low, high temperature stable contact resistance.
The finding has important consequences for the enhancement of reliability in
power devices as well as in Schottky-diodes and electrical contacts to silicon
in general.
