Conduction in magnesium phthalocyanine thin films with aluminium electrodes
Thin Film Lab., School of Pure and Applied Physics, Mahatma Gandhi University, 686 560 Kottayam, Kerala State, India
Corresponding author: a email@example.com
Revised: 3 June 2006
Published online: 21 August 2006
The various electrical properties and the nature of conduction mechanisms of magnesium phthalocyanine thin film devices with top and bottom aluminium electrodes have been investigated. The conduction mechanism was identified as injection limited essentially due to the electrode material. Even with the same electrode materials, the device showed asymmetric conduction behavior in the forward and reverse bias. In general the conduction was interpreted as a Schottky emission with barrier height Φs=1.07 eV for the forward bias and Φs=1.09 eV in the reverse bias. The effect of oxygen on the conductivity of the device has also been investigated. In the oxygen doped samples the conductivity is decreased which may be attributed to an interfacial layer between the electrode and the organic layer. Further in the oxygen doped sample while a Schottky emission is observed at lower voltages Poole-Frenkel conductivity was identified in the higher voltage region.
PACS: 73.50.Pz – Photoconduction and photovoltaic effects / 73.61.At – Metal and metallic alloys / 72.20.-i – Conductivity phenomena in semiconductors and insulators / 84.32.Ff – Conductors, resistors (including thermistors, varistors, and photoresistors)
© EDP Sciences, Società Italiana di Fisica, Springer-Verlag, 2006