ECE 4160 / 6260 – Fall 2023 | Prof. Gina Adam | TA: Davud Kazdal
LAB 5. Topographic measurements
In this lab activity, you will:
1) Distinguish between several techniques of performing topographic measurements at
the nanoscale
2) Extract quantitative information about 2D materials.
Software required:
ProfilmOnline
(available to use in browser at www.profilmonline.com/ , a free account is needed)
Experiments
The ProfilmOnline is a program for visualizing and analyzing three-dimensional images from
profilometers and AFMs. In this lab you will view and extract topographic information from:
1) an optical profilometer image of a height standard for nanoscale measurements
available in the ProfilmOnline public gallery
2) AFM images of graphene provided on Blackboard (courtesy of Summerfield, A. et al.
Strain-engineered graphene grown on hexagonal boron nitride by molecular beam
epitaxy. Scientific reports, 6, 22440, 2016. Raw data at University of Nottingham,
Public Research Data Repository, https://rdmc.nottingham.ac.uk/handle/internal/38 )
Task 1: Analyze the 3D image of a nanoruler obtained using an optical profilometer
After you have created an account and logged in, go to Community → Public Gallery
ECE 4160 / 6260 – Fall 2023 | Prof. Gina Adam | TA: Davud Kazdal
Then select the file “Nanoruler – High precision step height standard with nm steps”
by double clicking on it. You can now determine the height profile using “Slice”
function.
Q1: Estimate the heights of all the nanosteps. Include in your Lab Report #1 the
height vs. distance plot with the estimated values of all the 8 nanosteps.
Task 2: Analyze the AFM images of a graphene monolayer grown on hBN.
ECE 4160 / 6260 – Fall 2023 | Prof. Gina Adam | TA: Davud Kazdal
Note: The images for the following tasks are courtesy of Summerfield, A. et al.
Strain-engineered graphene grown on hexagonal boron nitride by molecular beam
epitaxy. Scientific reports, 6, 22440, 2016. The raw data is provided by the University
of Nottingham, Public Research Data Repository,
https://rdmc.nottingham.ac.uk/handle/internal/38.
They are also available on Blackboard for your convenience.
Since this is the raw data, you need to pre-process the image using the functionality
provided by typical AFM software before you can analyze the data. Use the options in
the menu below to obtain an image suitable for analysis.
ECE 4160 / 6260 – Fall 2023 | Prof. Gina Adam | TA: Davud Kazdal
ECE 4160 / 6260 – Fall 2023 | Prof. Gina Adam | TA: Davud Kazdal
ECE 4160 / 6260 – Fall 2023 | Prof. Gina Adam | TA: Davud Kazdal
Both graphene and hBN have a hexagonal
structure. When two regular patterns are
superimposed with a lattice mismatch or angle
twist or lattice mistmatch, a new pattern results
with a larger periodic lattice, called a Moiré
pattern or a Moiré superlattice.
Q2: Compare the estimated side length of the Moiré
superlattice with the C-C bond in graphene
(~0.142nm) and B-N bond in hBN (~0.144nm). How
many C atoms are in a superlattice unit? Include
the estimation and the reasoning in the Lab
Report #1.
Q3: Include the obtained image in the Lab Report #1
and mark the defects observed, discussing what
effects will this might have on the film and on its
properties?
ECE 4160 / 6260 – Fall 2023 | Prof. Gina Adam | TA: Davud Kazdal
Part. B. Go to “My Images → Upload image” to upload the image “G70_0129.ibw”
This image shows a crack in the graphene monolayer and you can use it to
measure its thickness based on what you learned from the instructions above
Hint: Pre-process the image accordingly. For the filtering, increase the cutoff length to ~0.25um.
Q4: Include in the Lab Report #1 the obtained 2D image, its 3D rendering as well as the
height vs. distance plot used to determine the thickness of the graphene.