Surface phonon scattering in epitaxial graphene on 6H-SiC

Surface phonon scattering in epitaxial graphene on 6H-SiC

Peer-reviewed article not indexed in WoS or Scopus

We show the growth of high-quality epitaxial graphene on 6H-SiC with Raman signatures comparable to exfoliated flakes. We ascribe the remaining low-quality transport properties to the strong electron-phonon coupling to two low-energy phonon modes at 70 and 16 meV. The coupling of these modes is enhanced by the defects present in the SiC substrate and buffer layer. Measurements of the mobility versus carrier concentration show a square-root dependence, corroborating the importance of surface phonon scattering in the limited mobility of graphene on SiC.

We show the growth of high-quality epitaxial graphene on 6H-SiC with Raman signatures comparable to exfoliated flakes. We ascribe the remaining low-quality transport properties to the strong electron-phonon coupling to two low-energy phonon modes at 70 and 16 meV. The coupling of these modes is enhanced by the defects present in the SiC substrate and buffer layer. Measurements of the mobility versus carrier concentration show a square-root dependence, corroborating the importance of surface phonon scattering in the limited mobility of graphene on SiC.

Graphene, SiC, Phonon scattring

Graphene, SiC, Phonon scattring

GIESBERS, A.; PROCHÁZKA, P.; FLIPSE, C.

2014

06.05.2013

1098-0121

PHYSICAL REVIEW B

87

19

United States of America

195405-1

195405-5

5