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arXiv · 2006.11202

Fabrication of nanocrystal superlattice microchannels by soft-lithography for electronic measurements of single crystalline domains

Andre Maier·Ronny Loeffler·Marcus Scheele
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Abstract

We report a high-throughput and easy-to-implement approach to fabricate microchannels of nanocrystal superlattices with dimensions of ~4 micrometer^2, thus approaching the size of typical single-crystalline domains. By means of microcontact printing, highly ordered superlattices with microscale dimensions are transferred onto photolithographically prepatterned microelectrodes, obtaining well-defined superlattice microchannels. We present step-by-step guidelines for microfabrication, nanocrystal self-assembly and patterning to archive large quantities of up to 330 microchannels per device for statistically meaningful investigations of charge transport in single-crystalline superlattice domains. As proof-of-concept, we perform conductivity and field-effect transistor measurements on microchannels of PbS nanocrystal superlattices. We find that the electric transport within microchannel superlattices is orders of magnitude more efficient than within conventional large-scale channels, highlighting the advantage of the near single-crystalline microchannels presented in this paper.

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Andre Maier, Ronny Loeffler, Marcus Scheele. 2020-06-19. Fabrication of nanocrystal superlattice microchannels by soft-lithography for electronic measurements of single crystalline domains. https://doi.org/10.1088/1361-6528/ab9c52

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