Low Temperature Sputtered Graphenic Carbon Enables Highly Reliable Contacts to Silicon

Titanium silicide (TiSi) contacts are commonly used metal- silicon contacts but are known to diffuse into the active region under high current stress. Recently we demonstrated that graphenic carbon (GC) deposited by CVD has the same low Schottky barrier on silicon as TiSi, but a much improved reliability against high current stress. The drawback of the CVD-GC is the required deposition temperature of ~ 900 °C. In this paper we demonstrate n ow that the deposition of graphenic carbon is possible at 100 - 400°C by a modified sputter process. We show that the sputtered carbon-silicon (SC-Si) contact is over 1 billion times more stable against high current stress pulses than the conventionally used TiSi-Si junction, while it has the same or even a lower Schottky barrier. Doping SC by nitrogen (CN) leads to an even lower resistivity and improved stability. The finding that there is a low temperature approach for using the superb carbon properties h as important consequences for the reliability of contacts to silicon and opens up the use of GC in a plethora of other applications.     «

Titanium silicide (TiSi) contacts are commonly used metal- silicon contacts but are known to diffuse into the active region under high current stress. Recently we demonstrated that graphenic carbon (GC) deposited by CVD has the same low Schottky barrier on silicon as TiSi, but a much improved reliability against high current stress. The drawback of the CVD-GC is the required deposition temperature of ~ 900 °C. In this paper we demonstrate n ow that the deposition of graphenic carbon is...     »