136
5 Optical Measurement Techniques
Fig. 5.2 Schematic diagram of a modified (commercial) invert microscope platform with attached
stacking unit for controlled 2D heterostructuring, optical control, imaging and spectroscopy capabilities, employed by Mey et al. in their works on 2D–grating structures [6]. Drawn in a similar fashion
as in [6] based on an author-team member’s visual interpretation. In-coupling of white thermal or
532-nm laser light from a side port allows one to monitor 2D materials during the dry-stamping
process and to excite monolayer luminescence optically for the clear identification of direct-gap
semiconductor flakes during production, respectively. In addition, a top illumination scheme can be
used. Note that laser light can permanently damage the eyes, if they are exposed to it. Thus, proper
and accurate eye-safety measures are mandatory and it is crucial to fully block the laser light for
eye safety on the imaging side of the device, in compliance with laser safety norms, and to filter
out the laser light from digital recordings by an imaging camera or spectrometer
instance, such combination can be used in order to reduce/exploit dependencies on
the sample location, or to enable spatially-selective excitation and detection. This in
turn can be used for raster scanning of signal correlated to a distinct sample position.
In most cases, microscopy is needed to image structures, surfaces and to monitor
the sample position. Particularly, its role in the materials-sciences and spectroscopy
communities has been revived in the era of 2D-materials stacking, for which visualisation of 2D materials under the microscope is essential for the manual stacking
process of layers.
As a practical microscope setup, one can typically use commercial platforms such
as inverted or conventional microscopes (cf. [6]) and self-constructed ones (cf. [7]).
For an extension of measurement options, input/output ports and a certain modularity
in commercial microscopes are required for the manipulation of optical pathways
and couplings, and the insertion of various types of filters.
A schematic overview on two different Optical setup is given in Figs. 5.2 and 5.3.
The setup with commercial inverted microscope features a 2D-materials stamping
section and a light-source in-coupling as well as signal detection section [6]. The
example of a home-built microscope features flexible incoupling pathways and a
two-times 4- f imaging configuration behind a microscope objective with multiple
exit opportunities towards different diagnostics tools [5, 7].
5 Optical Measurement Techniques
Fig. 5.2 Schematic diagram of a modified (commercial) invert microscope platform with attached
stacking unit for controlled 2D heterostructuring, optical control, imaging and spectroscopy capabilities, employed by Mey et al. in their works on 2D–grating structures [6]. Drawn in a similar fashion
as in [6] based on an author-team member’s visual interpretation. In-coupling of white thermal or
532-nm laser light from a side port allows one to monitor 2D materials during the dry-stamping
process and to excite monolayer luminescence optically for the clear identification of direct-gap
semiconductor flakes during production, respectively. In addition, a top illumination scheme can be
used. Note that laser light can permanently damage the eyes, if they are exposed to it. Thus, proper
and accurate eye-safety measures are mandatory and it is crucial to fully block the laser light for
eye safety on the imaging side of the device, in compliance with laser safety norms, and to filter
out the laser light from digital recordings by an imaging camera or spectrometer
instance, such combination can be used in order to reduce/exploit dependencies on
the sample location, or to enable spatially-selective excitation and detection. This in
turn can be used for raster scanning of signal correlated to a distinct sample position.
In most cases, microscopy is needed to image structures, surfaces and to monitor
the sample position. Particularly, its role in the materials-sciences and spectroscopy
communities has been revived in the era of 2D-materials stacking, for which visualisation of 2D materials under the microscope is essential for the manual stacking
process of layers.
As a practical microscope setup, one can typically use commercial platforms such
as inverted or conventional microscopes (cf. [6]) and self-constructed ones (cf. [7]).
For an extension of measurement options, input/output ports and a certain modularity
in commercial microscopes are required for the manipulation of optical pathways
and couplings, and the insertion of various types of filters.
A schematic overview on two different Optical setup is given in Figs. 5.2 and 5.3.
The setup with commercial inverted microscope features a 2D-materials stamping
section and a light-source in-coupling as well as signal detection section [6]. The
example of a home-built microscope features flexible incoupling pathways and a
two-times 4- f imaging configuration behind a microscope objective with multiple
exit opportunities towards different diagnostics tools [5, 7].