We report noncontact, optical determination of free-charge carrier mobility, sheet density, and resistivity parameters in epitaxial graphene at room temperature using terahertz and midinfrared ellipsometry and optical-Hall effect measurements. The graphene layers are grown on Si- and C-terminated semi-insulating 6H silicon carbide polar surfaces. Data analysis using classical Drude functions and multilayer modeling render the existence of a p-type channel with different sheet densities and effective mass parameters for the two polar surfaces. The optically obtained parameters are in excellent agreement with results from electrical Hall effect measurements.

1.
K. S.
Novoselov
,
A. K.
Geim
,
S. V.
Morozov
,
D.
Jiang
,
Y.
Zhang
,
S. V.
Dubonos
,
I. V.
Grigorieva
, and
A. A.
Firsov
,
Science
306
,
666
(
2004
).
2.
C.
Berger
,
Z.
Song
,
T.
Li
,
X.
Li
,
A. Y.
Ogbazghi
,
R.
Feng
,
Z.
Dai
,
A. N.
Marchenkov
,
E. H.
Conrad
,
P. N.
First
, and
W. A.
de Heer
,
J. Phys. Chem. B
108
,
19912
(
2004
).
3.
K. S.
Novoselov
,
A. K.
Geim
,
S. V.
Morozov
,
D.
Jiang
,
M. I.
Katsnelson
,
I. V.
Grigorieva
,
S. V.
Dubonos
, and
A. A.
Firsov
,
Nature (London)
438
,
197
(
2005
).
4.
Y. -M.
Lin
,
C.
Dimitrakopoulos
,
K. A.
Jenkins
,
D. B.
Farmer
,
H. -Y.
Chiu
,
A.
Grill
, and
P.
Avouris
,
Science
327
,
662
(
2010
).
5.
W. A.
de Heer
,
C.
Berger
,
X.
Wu
,
P. N.
First
,
E. H.
Conrad
,
X.
Li
,
T.
Li
,
M.
Sprinkle
,
J.
Hass
,
M. L.
Sadowski
,
M.
Potemski
, and
G.
Martinez
,
Solid State Commun.
143
,
92
(
2007
).
6.
H.
Fujiwara
,
Spectroscopic Ellipsometry
(
Wiley
,
New York
,
2007
).
7.
T.
Hofmann
,
C.
Herzinger
,
A.
Boosalis
,
T.
Tiwald
,
J.
Woollam
, and
M.
Schubert
,
Rev. Sci. Instrum.
81
,
023101
(
2010
).
8.
T.
Hofmann
,
U.
Schade
,
W.
Eberhardt
,
C. M.
Herzinger
,
P.
Esquinazi
, and
M.
Schubert
,
Rev. Sci. Instrum.
77
,
063902
(
2006
).
9.
J. L.
Tedesco
,
G. G.
Jernigan
,
J. C.
Culbertson
,
J. K.
Hite
,
Y.
Yang
,
K. M.
Daniels
,
R. L.
Myers-Ward
,
C. R.
Eddy
,
J. A.
Robinson
,
K. A.
Trumbull
,
M. T.
Wetherington
,
P. M.
Campbell
, and
D. K.
Gaskill
,
Appl. Phys. Lett.
96
,
222103
(
2010
).
10.
G. E.
Jellison
,
Thin Solid Films
313–314
,
33
(
1998
).
11.
T. E.
Tiwald
,
J. A.
Woollam
,
S.
Zollner
,
J.
Christiansen
,
R. B.
Gregory
,
T.
Wetteroth
,
S. R.
Wilson
, and
A. R.
Powell
,
Phys. Rev. B
60
,
11464
(
1999
).
12.
L.
Patrick
and
W. J.
Choyke
,
Phys. Rev. B
2
,
2255
(
1970
).
13.
Y.
Peng
,
X.
Xu
,
X.
Hu
,
K.
Jiang
,
S.
Song
,
Y.
Gao
, and
H.
Xu
,
J. Appl. Phys.
107
,
093519
(
2010
).
14.
M.
Schubert
,
Ann. Phys.
15
,
480
(
2006
).
15.
M.
Schubert
,
Infrared Ellipsometry on Semiconductor Layer Structures: Phonons, Plasmons and Polaritons
,
Springer Tracts in Modern Physics
Vol.
209
(
Springer
,
Berlin
,
2004
).
16.
M.
Schubert
,
T.
Hofmann
, and
J.
Šik
,
Phys. Rev. B
71
,
035324
(
2005
).
17.
C.
Pidgeon
, in
Handbook on Semiconductors
, edited by
M.
Balkanski
(
North-Holland
,
Amsterdam
,
1980
).
18.
C. M.
Wolfe
,
N.
Holonyak
, and
G. E.
Stillmann
,
Physical Properties of Semicoductors
(
Prentice Hall
,
Upper Saddle River, NJ
,
1989
).
19.
T.
Hofmann
,
C.
Herzinger
, and
M.
Schubert
,
Phys. Status Solidi A
205
,
779
(
2008
).
20.
M. K.
Yakes
,
D.
Gunlycke
,
J. L.
Tedesco
,
P. M.
Campbell
,
R. L.
Myers-Ward
,
C. R.
Eddy
,
D. K.
Gaskill
,
P. E.
Sheehan
, and
A. R.
Laracuente
,
Nano Lett.
10
,
1559
(
2010
).
21.
J. L.
Tedesco
,
B. L.
VanMil
,
R. L.
Myers-Ward
,
J. M.
McCrate
,
S. A.
Kitt
,
P. M.
Campbell
,
G. G.
Jernigan
,
J. C.
Culbertson
,
C. R.
Eddy
, Jr.
, and
D.
Gaskill
,
Appl. Phys. Lett.
95
,
122102
(
2009
).
22.
Note that the identification of different carrier channels in electrical Hall effect measurements requires magnetic field or temperature dependent measurements which were not performed here. Very recently, Lin et al identified up to three different carrier channels in magnetic field dependent electrical Hall effect measurements carried out on graphene samples grown on C-face SiC (Ref. 23).
23.
Y. -M.
Lin
,
C.
Dimitrakopoulos
,
D. B.
Farmer
,
S. -J.
Han
,
Y.
Wu
,
W.
Zhu
,
D. K.
Gaskill
,
J. L.
Tedesco
,
R. L.
Myers-Ward
,
J.
Charles
,
R.
Eddy
,
A.
Grill
, and
P.
Avouris
,
Appl. Phys. Lett.
97
,
112107
(
2010
).
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