A thin film of polymethylmetacrylate (PMMA) acting as a buffer layer has been employed in order to fabricate high-quality pentacene thin-film transistors (TFTs), both in bottom contact and top contact configuration. A PMMA buffer layer allows to reduce the interaction between a π-conjugated system of pentacene and the metal or dielectric substrate. We show that a thin PMMA buffer layer improves crystal quality along the metal contacts’ boundaries, while still allowing good ohmic contact. Pentacene TFTs, including a PMMA buffer layer, show very high field-effect mobility, μFE=0.65 and 1.4cm2Vs, for bottom and top contact configuration, respectively, and remarkable steep subthreshold region.

1.
H.
Klauk
,
M.
Halik
,
U.
Zschieschang
,
G.
Schimd
,
W.
Radik
, and
W.
Weber
,
J. Appl. Phys.
92
,
5259
(
2002
).
2.
H.
Klauk
,
M.
Halik
,
U.
Zschieschang
,
F.
Eder
,
G.
Schimd
, and
C.
Dehm
,
Appl. Phys. Lett.
82
,
4275
(
2003
).
3.
Y.
Kato
,
S.
Iba
,
R.
Teramoto
,
T.
Sekitani
,
T.
Someya
,
H.
Kawaguchi
, and
T.
Sakurai
,
Appl. Phys. Lett.
84
,
3789
(
2004
).
4.
C. J.
Drury
,
C. M. J.
Mutsaers
,
C. M.
Hart
,
M.
Matters
, and
D. M.
de Leeuw
,
Appl. Phys. Lett.
73
,
108
(
1998
).
5.
F.
Eder
,
H.
Klauk
,
M.
Halik
,
U.
Zschieschang
,
G.
Schimd
, and
C.
Dehm
,
Appl. Phys. Lett.
84
,
2673
(
2004
).
6.
T.
Minari
,
T.
Nemoto
, and
S.
Isoda
,
J. Appl. Phys.
96
,
769
(
2004
).
7.
J.
Lee
,
K.
Kim
,
J. H.
Kim
, and
S.
Im
,
Appl. Phys. Lett.
82
,
4169
(
2003
).
8.
F.
De Angelis
,
T.
Toccoli
,
A.
Pallaoro
,
N.
Coppedè
,
L.
Mariucci
,
G.
Fortunato
, and
S.
Iannotta
,
Synth. Met.
146
,
291
(
2004
).
9.
D.
Knipp
,
R. A.
Street
,
A.
Volkel
, and
J.
Ho
,
J. Appl. Phys.
93
,
347
(
2003
).
10.
V.
Podzorov
,
V. M.
Pudalov
, and
M. E.
Gershenson
,
Appl. Phys. Lett.
82
,
1739
(
2003
).
11.
More information on PMMA properties can be found, for instance, on the website http:∕∕www.allresist.de
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