Doping of graphene for the application in nano-interconnect

- Doping of graphene with acids can efficiently increase hole concentration through charge transfer process.
- Resistivity comparable to BEOL metals (e.g. Ru) can be achieved by doping CVD single-layer graphene.
- Mobility degradation after doping is observed for both single-layer graphene and few-layer graphene.
- A combination of long range and short range scattering can explain the mobility behavior of single-layer graphene.
- Doped CVD few-layer graphene shows lower mobility and higher sheet resistance than single-layer graphene.

Graphene is considered as potential candidate for future nano-interconnects. In this respect we study the Brønsted acid doping effect of single layer graphene (SLG) and few layer graphene (FLG) synthesized by chemical vapor deposition (CVD). A sheet resistance reduction of 50% is achieved by HNO3 doping of SLG, and the resulting resistivity of 9.1 μΩ·cm is comparable to alternative metals to copper (e.g. Ru). On the other hand, synthetic FLG shows higher sheet resistance due to higher defect density. Mobility degradation at increased carrier concentration is a main limiting factor for sheet resistance reduction of CVD graphene.

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