  Layered materials (LMs) such as graphene or MoS$_2$ have recently attracted a
great deal of interest. These materials offer unique functionalities due to
their structural anisotropy characterized by weak van der Waals bonds along the
out-of-plane axis and covalent bonds in the in-plane direction. A central
requirement to access the structural information of complex nanostructures
built upon LMs is to control the relative orientation of each sample prior to
their inspection e.g. with Transmission Electron Microscopy (TEM). However,
developing sample preparation methods that result in large inspection areas and
ensure full control over the sample orientation while avoiding damage during
the transfer to the TEM grid is challenging. Here we demonstrate the
feasibility of deploying ultramicrotomy for the preparation of LM samples in
TEM analyses. We show how ultramicrotomy leads to the reproducible large-scale
production of both in-plane and out-of-plane cross-sections, with bulk
vertically-oriented MoS$_2$ and WS$_2$ nanosheets as proof of concept. The
robustness of the prepared samples is subsequently verified by their
characterization by means of both high-resolution TEM and Raman spectroscopy
measurements. Our approach is fully general and should find applications for a
wide range of materials as well as of techniques beyond TEM, thus paving the
way to the systematic large-area mass-production of cross-sectional specimens
for structural and compositional studies.
