Applied Physics Letters · 2010 · 29 citations · 17 references
Natural SciencesMaterials SciencePhysicsCondensed Matter PhysicsElectrochemistryThin FilmsCarrier TransportCharge Carrier TransportSemiconducting MaterialsSemiconductor PhysicsSemiconductor Thin FilmsThin Film Electrical PropertiesCarrier Transport MechanismsCharge TransportCharge Transport MechanismsConductivity In Thin FilmsCurrent-voltage RelationsElectrical Transport PropertiesSemiconductor ConductivityTemperature-dependent Transport
The temperature dependent current-voltage (J-V) characteristics of highly-oriented cobalt phthalocyanine films (rocking-curve width=0.11°) deposited on (001) LaAlO3 substrates are investigated. In the temperature range 300–100 K, charge transport is governed by bulk-limited processes with a bias dependent crossover from Ohmic (J∼V) to trap-free space-charge-limited conduction (J∼V2). The mobility (μ) at 300 K has a value of ∼7 cm2 V−1 s−1 and obeys Arrhenius-type (ln μ∼1/T) behavior. However, at temperatures <100 K, the charge transport is electrode-limited, which undergoes a bias dependent transition from Schottky (ln J∼V1/2) to multistep-tunneling (conductivity varying exponentially on the inverse of the square-root of electric field).
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