Effect of high-K dielectrics on charge transport in graphene

TL;DR

This paper investigates how different dielectric materials affect charge mobility in graphene, revealing that high-K dielectrics reduce Coulomb scattering but introduce surface phonon scattering that limits mobility improvements.

Contribution

It provides a comprehensive analysis of dielectric effects on graphene charge transport, combining phonon and impurity scattering, and suggests strategies for mobility enhancement.

Findings

High-K dielectrics reduce Coulomb impurity scattering.

Surface phonon modes from dielectrics limit mobility gains.

Comparison with III-V semiconductors offers mobility improvement strategies.

Abstract

The effect of various dielectrics on charge mobility in single layer graphene is investigated. By calculating the remote optical phonon scattering arising from the polar substrates, and combining it with their effect on Coulombic impurity scattering, a comprehensive picture of the effect of dielectrics on charge transport in graphene emerges. It is found that though high-$\kappa$ dielectrics can strongly reduce Coulombic scattering by dielectric screening, scattering from surface phonon modes arising from them wash out this advantage. By comparing the room-temperature transport properties with narrow-bandgap III-V semiconductors, strategies to improve the mobility in single layer graphene are outlined.