Substrate effect on graphene-based interconnects

We investigated major performance metrics of graphene interconnects on 2D layered insulator - hexagonal boron nitride (h-BN). Comparative study was made on three different material systems, including CVD graphene on h-BN, CVD graphene on SiO
₂
, and exfoliated graphene on SiO
₂
, with respect to electrical conduction and breakdown power density. Remarkable improvement in conductivity is observed in CVD graphene on h-BN substrate as compared with CVD graphene on SiO
₂
and exfoliated graphene on SiO
₂
. The carrier mobility in CVD graphene on h-BN exhibits a value of ~15,000 cm
²
/V-s at carrier density of 1×10
¹²
cm
^-2
. Higher thermal conductivity of h-BN (as compared with that of SiO
₂
) facilitates heat dissipation, leading to improvement in breakdown power density. It is demonstrated that using h-BN as substrate material could help breaking the performance and reliability limits imposed by SiO
₂
substrate.