ICSPI nGauge User manual

nGauge Atomic Force Microscope
User Manual Version 2.0
For Software and Firmware versions 1.0.0.0

© ICSPI Corp. 2007-2021 nGauge AFM User Manual 2.0 2
Table of Contents
1. Introduction..........................................................................................................................4
2. Safety and Precautions........................................................................................................4
3. Overview..............................................................................................................................7
3.1. AFM Basics...................................................................................................................7
3.2. MEMS AFM or AFM-on-a-Chip.....................................................................................7
3.3. nGauge AFM Components ...........................................................................................8
3.4. nGauge AFM Capabilities.............................................................................................8
4. Setup.................................................................................................................................10
4.1. Location......................................................................................................................10
4.2. Basic Set-up ...............................................................................................................11
4.3. Software Installation....................................................................................................12
5. Basic Operation .................................................................................................................13
5.1. Start-up.......................................................................................................................13
5.2. Chip Installation and Sample Placement.....................................................................14
5.3. Software Overview......................................................................................................17
5.4. Sweep.........................................................................................................................17
5.5. Approach ....................................................................................................................19
5.6. Scan ...........................................................................................................................23
5.7. Scanning Recommendations ......................................................................................29
5.8. Improving Performance...............................................................................................33
5.9. Advanced Scan Features............................................................................................36
6. Post-Processing.................................................................................................................38
6.1. Gwyddion....................................................................................................................39
6.2. Calibration...................................................................................................................40
7. Troubleshooting.................................................................................................................42
7.1. Set-up Troubleshooting...............................................................................................42
7.2. Sweep Troubleshooting ..............................................................................................44
7.3. Approach Troubleshooting..........................................................................................48
7.4. Scan Troubleshooting.................................................................................................52
8. Advanced Controls.............................................................................................................55
8.1. Sweep Advanced Controls..........................................................................................55
8.2. Approach Advanced Controls......................................................................................57

© ICSPI Corp. 2007-2021 nGauge AFM User Manual 2.0 3
8.3. Menu Button Advanced Controls.................................................................................58
9. Appendix............................................................................................................................61
9.1. Gwyddion Supplement................................................................................................61

© ICSPI Corp. 2007-2021 nGauge AFM User Manual 2.0 4
1.Introduction
Congratulations on purchasing an nGauge Atomic Force Microscope!
The nGauge AFM achieves magnification that far surpasses that of an optical microscope so
you can explore the world with nanometer-scale resolution.
The most up-to-date user manual can be downloaded from the ICSPI website at
https://www.icspicorp.com/resources
Please read the user manual before operating your new instrument to learn how it works, how to
set up and operate the hardware and software, how to prepare samples, and how to visualize
your data.
2.Safety and Precautions
The following warnings and precautions should be observed to ensure the safety of the user
and the instrument:
•Use only the power supply provided. The driving electronics are designed to accept
7.5 V (DC) and an internal fuse prevents the input current from exceeding 1 A.
•The stage contains moving parts that could pinch. To avoid minor injury, be aware of
the moving parts.
•Do not disassemble the system. Except for sample platform customization,
disassembly of the system voids the warranty and could result in damage to the
electronics or the mechanical components.
•Be extremely careful when handling an AFM chip. They are very fragile and will
break if the tip is touched. AFM chips should be stored in their box with the tip facing
DOWN and removed using the tweezers provided. If necessary, the AFM chip can be
placed on a flat surface with the tip facing up. The AFM chip can be picked up by hand
by the board as long as you are careful to avoid touching the tip.
The tip, located at the edge of the
board, is extremely fragile.

© ICSPI Corp. 2007-2021 nGauge AFM User Manual 2.0 5
AFM chips should be stored with the
tip facing down in the storage box.
Use tweezers to pick them up.
The AFM chip can be placed on a
flat surface with the tip facing up.
The AFM chip can be picked up by
hand as long as you don't touch the
tip.
This is a zoomed-in photo of the
AFM chip. The chip is extremely
fragile.

© ICSPI Corp. 2007-2021 nGauge AFM User Manual 2.0 6
Sample should not move during scanning
Make sure that the sample is stable and will
not move during scanning.
Lightweight samples should be mounted
onto a rigid substrate like a glass slide or
metal disc.
Keep the chip a safe distance from the sample
When installing or removing a chip, make
sure that there is at least 5 mm of space
between the tip and the sample.
To retract the tip in the software, go to the
Approach page and click and hold the
Retract button.
Probe tip is susceptible to damage when engaged
Do not touch the sample, chip or unit when
the tip is approaching or in contact with the
sample. The probe tip is susceptible to
damage when approaching or engaged.
Minimize contact between tip and sample
Minimize the amount of time that the tip is
contact with the sample. When you are
finished scanning, navigate to the Approach
page:
1. Click on Disengage.
2. Wait for the button to indicate Retract.
3. Click and hold on Retract until the tip is
at least 5 mm away from the sample (about
10 seconds).
1
2
DISENGAGE
RETRACT

© ICSPI Corp. 2007-2021 nGauge AFM User Manual 2.0 7
3. Overview
3.1. AFM Basics
Unlike optical microscopes that use light and lenses to magnify, or electron microscopes which
use electron beams to generate an image, an atomic force microscope (AFM) uses a very sharp
tip to scan across the surface of a sample. AFM measures tip-sample interaction forces and
generates a 3D reconstruction of a sample surface.
This scan moves in X and in Y. It moves quickly from left to right (in the X direction, also known
as the fast scan axis), then moves backwards (reverses), and moves down to the next row (Y
direction) in the slow scan axis. The pattern is known as a raster scan.
A controller maintains a constant tip-sample force by adjusting the tip's Z height. The control
effort then represents the height of the features on the sample.
Conventional AFMs typically use a probe with a sharp tip on a silicon cantilever. A laser beam is
reflected off the backside of the cantilever onto a photodetector that measures any small
displacements of the cantilever. A piezoelectric Z-scanner controls the height of the probe while
a piezoelectric XY stage raster scans the sample in X and Y.
3.2. MEMS AFM or AFM-on-a-Chip
MEMS AFM or AFM-on-a-chip operates almost exactly like a conventional AFM except that all
of the essential components are integrated onto a single chip. The nGauge AFM chip is a micro
-electro-mechanical systems (MEMS) device that uses the most advanced manufacturing
process in the world to produce tiny, ultra-precise scanners and sensors on a 1 mm x 1 mm
silicon chip.
An AFM on a chip has a cantilever and a sharp tip but instead of a laser it has an integrated
piezoresistive strain sensor to measure tip displacements. The tip and sensor are attached to a
MEMS scanner that can position them in X, Y, and Z with sub-nanometer resolution.

© ICSPI Corp. 2007-2021 nGauge AFM User Manual 2.0 8
3.3. nGauge AFM Components
The nGauge AFM system includes all of the following components. A computer (not included)
with a USB port is required and access to a power outlet.
1. Stage
2. Sample Platform
3. Thumb Nut
4. AFM Chips
5. Power Supply
6. USB Cable
7. Tweezers
3.3.1. Detachable Sample Platform
nGauge AFM models 1.1 and 1.2 feature a detachable sample platform. These screws are
removable, and the stage can be customized.
3.3.2. Hole in base plate
The base plate features a hole for mounting the nGauge AFM onto an optical table.
3.4. nGauge AFM Capabilities
3.4.1. Scan Mode
The nGauge AFM operates in tapping mode (also known as intermittent contact or dynamic
mode): the cantilever oscillates at its resonant frequency and makes intermittent contact or
“taps” the sample surface.
The nGauge AFM uses the amplitude of oscillation as the feedback mechanism, also known as
amplitude-modulation AFM (AM-AFM) mode.
The nGauge generates topography, phase and error images simultaneously.

© ICSPI Corp. 2007-2021 nGauge AFM User Manual 2.0 9
3.4.2. Scan Operation Environment
The nGauge AFM is designed to operate in ambient environment (normal room temperature
and pressure).
3.4.3. Scan Size
The nGauge AFM can scan areas of up to 20 µm x 20 µm in X and Y, up to 60 µm in X and
vertical distances up to 10 µm in Z (peak-to-valley) with <1 nm RMS noise in the vertical
direction.
3.4.4. Sample Types
Any solid sample can be imaged, including both conductive and non-conductive, but the
nGauge AFM cannot operate in liquid and cannot image liquid samples.
Some samples that are prone to surface charging, such as highly electrically resistive polymers,
may require a way to mitigate surface charging.
The maximum sample size for the normal sample platform is 100 mm × 50 mm × 16 mm
L×W×H.
The maximum sample weight is 1 kg.

© ICSPI Corp. 2007-2021 nGauge AFM User Manual 2.0 10
4.Setup
4.1. Location
The nGauge AFM is small, simple, and portable, and can be set up virtually anywhere. For best
results, it is recommended that you follow these guidelines:
Normal
temperature
and pressure
The nGauge system should be set up in areas with normal room
temperature and pressure.
Flat surface
The nGauge system should be set up on a flat, level surface, like a desk or
tabletop, with enough space to ensure that the stage does not get bumped
or moved while imaging.
Vibrations
The unique design of the nGauge AFM minimizes the effects of common
sources of low-frequency vibrations, such as those caused by people
walking by, doors opening and closing, and building vibrations. However, it is
best to set the system up on a solid, stable surface away from as many
sources of vibration as possible. The corner of a room is a good choice.
Air drafts
The system is not immune to air drafts and should be set up away from air
vents, drafty windows, etc. If possible, set up the nGauge AFM in the corner
of a room or near a wall where there is less air flow. If air drafts are
unavoidable and present a significant problem, a box or enclosure around
the system may be required.
Electrical
noise
The system meets the FCC guidelines for electrical interference, but it is
best to avoid setting it up near sources of electrical noise, such as server
rooms or rooms operating high-power equipment.