Theory of Band Gaps in Amorphous Nano-porous SiC*

Nano-porous SiC is an important insulator used as a back-end-of-the-line dielectric in scaled integrated circuits. In the present study, nano-porous SiC atomic models are created from cubic SiC supercells. First, a void of diameter of ~ 1 nm is hydrogen passivated. Then, amorphous models ae constructed with an atom type switching procedure, which was applied until the average atomic composition and bond densities converge to experimental values. Density functional theory calculations are used to explore the electronic and physical properties of various nano-porous SiC models. Specifically, we examine the effect of average atom composition and bonding on the bandgap of nano-porous SiC.