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arXiv · 1704.08038

Cleaning graphene: comparing heat treatments in air and in vacuum

Mukesh Tripathi·Andreas Mittelberger·Kimmo Mustonen·Clemens Mangler·Jani Kotakoski·Jannik C. Meyer·Toma Susi
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Abstract

Surface impurities and contamination often seriously degrade the properties of two-dimensional materials such as graphene. To remove contamination, thermal annealing is commonly used. We present a comparative analysis of annealing treatments in air and in vacuum, both ex situ and "pre-situ", where an ultra-high vacuum treatment chamber is directly connected to an aberration-corrected scanning transmission electron microscope. While ex situ treatments do remove contamination, it is challenging to obtain atomically clean surfaces after ambient transfer. However, pre-situ cleaning with radiative or laser heating appears reliable and well suited to clean graphene without undue damage to its structure.

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Mukesh Tripathi, Andreas Mittelberger, Kimmo Mustonen, Clemens Mangler, Jani Kotakoski, Jannik C. Meyer, Toma Susi. 2017-04-26. Cleaning graphene: comparing heat treatments in air and in vacuum. https://doi.org/10.1002/pssr.201700124

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