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arXiv · 1311.0988

Nucleation and growth of HfO$_2$ layers on graphene by CVD

Grzegorz Lupina·Mindaugas Lukosius·Julia Kitzmann·Jarek Dabrowski·Andre Wolff·Wolfgang Mehr
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Abstract

A seed layer-free growth of HfO$_2$ on commercially available CVD graphene from various suppliers is investigated. It is revealed that the samples of monolayer graphene transferred from Cu to SiO$_2$/Si substrates have different coverage with bi- and multi-layer graphene islands. We find that the distribution and number of such islands impact the nucleation and growth of HfO$_2$ by CVD. In particular, we show that the edges and surface of densely distributed bi-layer graphene islands provide good nucleation sites for conformal CVD HfO$_2$ layers. Dielectric constant of 16 is extracted from measurements on graphene- HfO$_2$-TiN capacitors.

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Grzegorz Lupina, Mindaugas Lukosius, Julia Kitzmann, Jarek Dabrowski, Andre Wolff, Wolfgang Mehr. 2013-11-05. Nucleation and growth of HfO$_2$ layers on graphene by CVD. https://doi.org/10.1063/1.4828660

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