Schottky contact on a ZnO (0001) single crystal with conducting polymer

• Published in: Applied physics letters Vol. 91; no. 14; pp. 142113 - 142113-3
• Main Authors: Nakano, M., Tsukazaki, A., Gunji, R. Y., Ueno, K., Ohtomo, A., Fukumura, T., Kawasaki, M.
• Format: Journal Article
• Language: English
• Published: American Institute of Physics 01-10-2007
• ISSN: 0003-6951; 1077-3118
• DOI: 10.1063/1.2789697

High quality Schottky junctions were fabricated on a ZnO (0001) bulk single crystal by spin coating a commercial conducting polymer, poly(3,4-ethylenedioxythiophene): poly(styrenesulfonate) (PEDOT:PSS), as the metal electrodes. The junctions exhibited excellent rectifying behavior with a typical ideality factor of 1.2. Such parameters as Schottky barrier height
(
ϕ
b
)
and built-in potential
(
V
bi
)
show negligible variation among junctions. The electron affinity of ZnO derived from
ϕ
b
and
q
V
bi
values show a slight deviation
(
∼
0.2
eV
)
, suggesting the existence of spontaneously formed interfacial dipole layer between ZnO (0001) polar surface and anionic PSS molecules.