journal article·2013-12

Trap healing and ultralow-noise Hall effect at the surface of organic semiconductors

B. Lee, Y. Chen, D. Fu, H. T. Yi, K. Czelen, H. Najafov, V. Podzorov

Nature Materials· Volume 12· Issue 12
Publisher page

Abstract

Fundamental studies of intrinsic charge transport properties of organic semiconductors are often hindered by charge traps associated with static disorder present even in optimized single-crystal devices. Here, we report a method of surface functionalization using an inert non-conjugated polymer, perfluoropolyether (PFPE), deposited at the surface of organic molecular crystals, which results in accumulation of mobile holes and a 'trap healing' effect at the crystal/PFPE interface. As a consequence, a remarkable ultralow-noise, trp-free conduction regime characterized by intrinsic mobility and transport anisotropy emerges in organic single crystals, and Hall effect measurements with an unprecedented signal-to-noise ratio are demonstrated. This general method to convert trap-dominated organic semiconductors to intrinsic systems may enable the determination of intrinsic transport parameters with high accuracy and make Hall effect measurements in molecular crystals ubiquitous.
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Research context

OpenAlex topics: Organic Electronics and Photovoltaics · Advanced Memory and Neural Computing · Quantum and electron transport phenomena

SciVX discovery tags are terminology-based. OpenAlex topics are source-provided classifications.

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