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arXiv · 0909.4010

Temperature-dependent transition from injection-limited to space-charge-limited current in metal-organic diodes

Yi Zheng·Andrew T. S. Wee·Cedric Troadec·N. Chandrasekhar
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Abstract

Based on the assumption that the contact barrier height determines the current flow in organic semiconductor-based electronic devices, charge injection at metal-organic (MO) interfaces has been extensively investigated, while space-charge conduction in organic bulk is generally overlooked. Recent theoretical modeling and simulation have pointed out that such a simplification is questionable due to the hopping nature of charge injection and hopping-related space-charge conduction. Here we show experimentally that charge transport in metal-organic diodes is complex interplay between injection-limited current (ILC) and space-charge-limited current (SCLC). We report the experimental observation of ILC-to-SCLC transition in Ag/pentacene/Ag diodes as a function of temperature.

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Yi Zheng, Andrew T. S. Wee, Cedric Troadec, N. Chandrasekhar. 2009-09-22. Temperature-dependent transition from injection-limited to space-charge-limited current in metal-organic diodes. https://doi.org/10.1063/1.3243844

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