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Titanium silicide (TiSi) contacts are frequently used metal-silicon contacts but are known to diffuse into the active region under high current density stress pulses. Recently, we demonstrated that graphenic carbon (GC) deposited by CVD at 1000 • C on silicon has the same low Schottky barrier as TiSi, but a much improved reliability against high current density stress pulses. In this paper, we demonstrate now that the deposition of GC is possible at 100 • C − 400 • C by a sputter process. We show that the sputtered carbon-silicon contact is over 1 billion times more stable against high current density pulses than the conventionally used TiSi-Si junction, while it has the same or even a lower Schottky barrier. SC can be doped by nitrogen (CN) and this results in an even lower resistivity and improved stability. Scalability of the CN thickness down to 5 nm is demonstrated. The finding that there is a low temperature approach for using the excellent carbon properties has important consequences for the reliability of contacts to silicon and opens up the use of GC in a vast number of other applications.

The wet anisotropic etching process is generally used in the field of micromachining (MEMS), particularly for commercial products such as accelerometers. Hard masks like oxide or nitride play a key role in the transfer of patterns to the substrate during the lithography process. This work reports on the use of polycrystalline graphenic carbon as an etch mask for wet chemical processing and outlines a simple method to create patterned structures on (100) silicon wafers. Graphenic carbon (GC) was deposited on the silicon substrate by chemical vapor deposition (CVD) using C2H4 as precursor. The desired pattern was written in the spin-coated negative photoresist using UV laser lithography. Different geometrical shapes were printed on the substrate with dimensions ranging from 10 to 50 micrometers. In the next stage, the O2 plasma etched away the carbon from the area not covered by the photoresist, acting as an additional mask for this and the subsequent processing steps. Finally, the sample was immersed in the KOH bath saturated with isopropanol and the etching rate was evaluated for each crystal plane. Compared to the use of a sacrificial oxide mask, this technique is simpler and produces more reliable results.