Journal Article

Exploring dielectric properties in atomistic models of amorphous boron nitride

Colombo, Luigi, Charlier, Jean-Christophe, Roche, Stephan, Dubois, Simon M-M, Galvani, Thomas, Shin, Yongwoo, Caputo, Laura, Hamze, Ali K., Nguyen, Viet-Hung, Shin, Hyeon-Jin, Kaya, Onurcan

2024

Overview

Abstract We report a theoretical study of dielectric properties of models of amorphous Boron Nitride, using interatomic potentials generated by machine learning. We first perform first-principles simulations on small (about 100 atoms in the periodic cell) sample sizes to explore the emergence of mid-gap states and its correlation with structural features. Next, by using a simplified tight-binding electronic model, we analyse the dielectric functions for complex three dimensional models (containing about 10.000 atoms) embedding varying concentrations of sp 1 , sp 2 and sp 3 bonds between B and N atoms. Within the limits of these methodologies, the resulting value of the zero-frequency dielectric constant is shown to be influenced by the population density of such mid-gap states and their localization characteristics. We observe nontrivial correlations between the structure-induced electronic fluctuations and the resulting dielectric constant values. Our findings are however just a first step in the quest of accessing fully accurate dielectric properties of as-grown amorphous BN of relevance for interconnect technologies and beyond.

• Publisher: IOP Publishing