Products

HR AFM

High Resolution Atomic Force Microscope For Research

The HR AFM is an advanced yet affordable AFM for researchers who need the highest resolution scanning capabilities on a wide range of sample types. $46,000 – $95,000

HR-AFM for nanomaterials characterization

Why an HR AFM?

Customers purchase the HR AFM because of its very low noise floor (<35 pm in a suitable environment) while maintaining the flexibility to scan bulky samples and the option to perform measurements in liquids. Research and quality control applications from single molecules to microbes, cells, and larger biomaterials are a great fit for the HR AFM.

We measured this image of nanoparticulates in distilled water deposited on mica. Note the height of the particles is ~500 pm.

molecular particulates from distilled water on mica

Overview

Sample Sizes Up to 1″ X 1″ X 1/2″
Standard Scanning Modes Vibrating (Tapping), Non-Vibrating (Contact), Phase, LFM
Scanners 100 X 100 X 17 µm, 50 X 50 X17 µm, 15 X 15 X 7 µm
Video Optical Microscope Top View: 400 X Research Grade, Side View: 200 X Cell Phone Type
Stage and EBox Size Compact table top design
Download: HR AFM Product Datasheet

Features of the HR AFM include:

Low Noise Floor

With a noise floor of 35 picometers the HR AFM is capable of measuring samples with features from nano-meters to microns.

Kinematic Tip Approach

A stable kinematic design for probe approach is used in the HR AFM. An optional direct drive approach is available.

Research Grade Top View Video Optical Microscope

With a mechanical 7:1 zoom and a resolution of 2 µm the video optical microscope facilitates locating features, tip approach, and laser alignment.

Multiple Scanners

Linearized piezoelectric scanners with several ranges are available to optimize scanning conditions.

LabView Software

The HR AFM uses industry standard lab view software. For customization, the systems VI’s are readily available.

Modular Design

Once you buy the HR AFM you can add options and modes such as focus assist, image logger, lithography and liquid scanning when you are ready.

Simple Probe Exchange

With the removable probe holder exchanging probes is simple and takes less than a minute.

Light Lever Large Adjustment Range

Because the HR AFM has a large adjustment range on the laser and photodetector, probes from all major manufacturers can be used.

Side View Optic

Directly view the tip surface distance with the side view optic.

HR AFM Applications

Applications for the AFM include imaging:

  • Biomolecules (DNA, proteins)

  • Nanoparticles (viruses)
  • Nanostructures (carbon nanotubes)
  • 2-D Materials (substrates)

  • Force measurements

Stage

The HR AFM stage has excellent thermal and mechanical stability required for high resolution AFM scanning. Additionally, its open design facilitates user modification.

Rigid Kinematic Design

A three point support for the light lever makes the AFM less suceptable to vibrations, enabling ultra high resolution scanning.

Light Lever AFM Force Sensor

Light lever force sensors are used in almost all AFM and permit many types of experiments.

Integrated Probe Holder/Probe Exchanger

A unique probe holder and clipping mechanism allows quick and easy probe exchange.

Z Drive Options

The standard HR AFM uses a single approach motor, the optional Z drive design uses four motors, enabling vertical approach and has a motorized video microscope.

Small Footprint

The stage dimensions of 9″ X 11″ require little space and fit easily on a tabletop.

Precision XY Stage with Micrometer

The sample is moved relative to the probe with a precision XY micrometer stage. Thus, the sample can be positioned without touching the probe.

Modes Electric Plug

A six pole electrical plug is located at the back of the stage to expand the capabilities of the HR AFM.

XYZ Precision Piezo Scanner

The modified tripod design utilizes temperature compensated strain gauges which assure accurate measurements from images and allow the user to rapidly zoom into a feature within an image.

Laser/Detector Alignment

Both the light lever laser and the photo detector adjustment mechanism may be directly viewed. This feature simplifies the laser/detector alignment.

Adaptable Sample Holder

At the top of the XYZ scanner is a removable cap that holds the sample. The cap can be modified – or a new cap can be designed – to hold many types of samples.

Rapid Approach Control

The rapid approach control allows moving the probe from within a few hundred microns from the surface to a mm in less than a second. Below is side view video optical microscope view of the rapid approach control in the “stage down” and “stage up” positions.

In the stage down position, the probe is within a few hundred microns of the surface. Activating the Rapid Approach Control immediately lifts the probe away from the surface.

This a side view of the probe in the stage up position. In the up position the probe and sample are readily exchanged.

Ebox

Electronics in the HR AFM are constructed around industry standard USB data acquisition electronics. The critical functions, such as XY scanning, are optimized with a 24-bit digital to analog converter. With the analog Z feedback loop, the highest fidelity scanning is possible. Vibrating mode scanning is possible with both phase and amplitude feedback using the high sensitivity phase detection electronics.

24 bit scan DAC

Scanning waveforms for generating precision motion in the X-Y axis with the piezo scanners are created with 24 bit DACS driven by a 32 bit micro controller. With 24 bit scanning, the highest resolution AFM images may be measured. Feedback control using the XY strain gauges assures accurate tracking of the probe over the surface.

Phase and Amplitude Detector Circuit

Phase and amplitude in the EBox are measured with highly stable phase and amplitude chips. The system can be configured to feed back on either phase or amplitude when scanning in vibrating mode.

Signal Accessible
At the rear of the EBox is a 50 pin ribbon cable that gives access to all of the primary electronic signals without having to open the EBox.
Precision Analog Feedback
Feedback from the light lever force sensor to the Z piezoceramic is made using a precision analog feedback circuit. The position of the probe may be fixed in the vertical direction with a sample-and-hold circuit.
Variable Gain High Voltage Piezo Drivers
An improved signal to noise ratio, as well as extremely small scan ranges are possible with the variable gain high voltage piezo drivers.

Software

The software for acquiring images is designed with the industry standard LabVIEW™ programming visual interface instrument design environment. There are many standard functions, including setting scanning parameters, probe approach, frequency tuning, and displaying images in real time. LabVIEW™ facilitates rapid development for those users seeking to enhance the software with additional special features. LabVIEW also enables the HR AFM to be readily combined with any other instrument using LabVIEW.

All of the functions required before making a scan are on the pre-scan tab. This includes selecting the scan mode, red dot alignment, frequency scan, and automatic tip approach.

Images are acquired using the scanning tab. Parameters selected on the scanning tab include the scan size, scan rate, GPID parameters, and the color scale used for displaying images. Included with the scanning tab is an image buffer capability that facilitates in-zooming and out-zooming.

Software control for optional modes such as MFM, EFM, and advanced F/D are found in the modes tabs. The example shown here is of the advanced F/D mode tab. This allows fine control of all the parameters controlling acquisition of force-distance curves, as well as acquisition of F-D curve maps. Mapping of curve sin this way allows the user to locate and visualize regions of the sample with varying properties, such as presence of specific molecules, or mechanical properties.

Image Analysis Software

Included with the HR AFM is the Gwyddion open source SPM image analysis software. This complete image analysis package has all the software functions necessary to process, analyze, and display SPM images.

  • Visualization: false color representation with different types of mapping
  • Shaded, logarithmic, gradient- and edge-detected, local contrast representation, and Canny lines
  • OpenGL 3D data display: false color or material representation
  • Easily editable color maps and OpenGL materials
  • Basic operations: rotation, flipping, inversion, data arithmetic, crop, and resampling
  • Leveling: plane leveling, profiles leveling, three-point leveling, facet leveling, polynomial background removal, leveling along user-defined lines
  • Value reading, distance, and angle measurement
  • Profiles: profile extraction, measuring distances in profile graph, and profile export
  • Filtering: mean, median, conservative denoise, Kuwahara, minimum, maximum, and checker pattern removal
  • General convolution filter with user-defined kernel
  • Statistical functions: Ra, RMS, projected and surface area, inclination, histograms, 1D and 2D correlation functions, PSDF, 1D and 2D angular distributions, Minkowski functionals, and facet orientation analysis
  • Statistical quantities calculated from area under arbitrary mask
  • Row/column statistical quantities plots
  • ISO roughness parameter evaluation
  • Grains: threshold marking and un-marking, and watershed marking
  • Grain statistics: overall and distributions of size, height, area, volume, boundary length, and bounding dimensions
  • Integral transforms: 2D FFT, 2D continuous wavelet transform (CWT), 2D discrete wavelet transform (DWT), and wavelet anisotropy detection
  • Fractal dimension analysis
  • Data correction: spot remove, outlier marking, scar marking, and several line correction methods (median, modus)
  • Removal of data under arbitrary mask using Laplace or fractal interpolation
  • Automatic XY plane rotation correction
  • Arbitrary polynomial deformation on XY plane
  • 1D and 2D FFT filtering
  • Fast scan axis drift correction
  • Mask editing: adding, removing or intersecting with rectangles and ellipses, inversion, extraction, expansion, and shrinking
  • Simple graph function fitting, critical dimension determination
  • Force-distance curve fitting
  • Axes scale calibration
  • Merging and immersion of images
  • Tip modeling, blind estimation, dilation and erosion

Video Microscope

The HR AFM includes two video optical microscopes for viewing the sample and probe. The video microscopes are essential for locating features on a surface, a safe and efficient probe approach, and aligning the light lever force sensor.

Top View Video Microscope

From the top, the HR AFM has a research grade video optical microscope with a 7:1 mechanical zoom, a 5 MP camera, and coaxial illumination. With a resolution of < 2 microns, this microscope is ideal for locating features on a surface for scanning.

With a 7:1 mechanical zoom, it is possible to use a large field of view to locate features for imaging. It is then possible to zoom in to get very high resolution video microscope images.

Side View Video Microscope

The side view video microscope has a 2 MP camera and an off axis LED light source and is used for visualizing the distance between the probe and the sample. This microscope is especially helpful for assisting probe approach on transparent and non-reflective samples.

Probe Holder

The HR AFM utilizes a unique probe holder/exchange mechanism. Probes are held in place with a spring device and exchanged with a probe exchange tool. Changing probes is simple and can be done in less than a minute.

Quick and Easy AFM Probe Exchange

The probe holder insert is removed from the HR AFM.
R to L: Box of probes, probe exchange tool, and probe holder insert.
Activating the probe spring clip by applying light pressure.

Gallery

The true measure of an AFM is the quality of images it measures. With a noise floor of less than 35 picometers, and 28 bit scanning resolution, the HR AFM is capable of measuring the highest resolution images on many types of samples including biomolecules such as DNA and individual proteins, nanostructured substrates, polymers and other biomaterials.

Vibrating mode image of F10H20 measured with a 50 X 50 X 17 micron scanner
2 X 2 microns
500 X 500 nm
250 X 250 nm
More Images
Vibrating mode images of collagen fibrils; 3µm × 3µm × 19.8 nm
4 X 4 nm image of Teflon; Courtesy of Grapes Technology
Graphene on crystalline nickel surface
12 × 12 micron scan of a polymer blend
8 × 8 µm image of polymeric nanocapsules
Indium Tin Oxide electrode surface; 1.3 µm × 1.3 × µm × 21 nm
Individual dsDNA molecule; 250 × 250 × 1.2 nm scan
Highly linear scan of silicon reference sample
1 X 1 u image of cylic DNA with bound protein; Courtesy of Justin Peters; University of North Iowa
Network of DNA molecules, 1 µm × 1µm × 3.5 nm micron scan
50 X 50 micron image of WSe2 triangle; Courtesy of Masoud Mahjouri Saman, Auburn University
4 X 4 micron image of Graphene on Si
Loading the next set of gallery items...
Load More

Modes

Scanning Modes

The HR AFM includes the most commonly used AFM Modes. The are:

Vibrating Mode (tap)

Vibrating mode imaging is the most common mode for measuring topography images with an AFM. In vibrating mode the vibration amplitude of the probe is held constant during a scan. Adjustable parameters include the vibrating frequency, amplitude of vibration, and the amount of dampening of the vibrating probe.

Non-vibrating (contact)

In non-vibrating mode, commonly called contact mode, the deflection of a cantilever is held constant during scanning. This mode is often used for scanning in liquids and is also used for measuring force-distance curves.

Phase

Phase mode images are measured in vibrating mode and are useful for identifying different areas of hardness on a surface. The technique operates by measuring the phase change caused by various materials on a surface while scanning.

Lateral Force

Lateral force mode measures the local friction a probe senses as it is scanned across a surface. The friction can be caused by surface texture or by different chemical composition.

Force – Distance (F/D)

Force Distance Curves measure the deflection of a cantilever as it interacts with a surface. Force-Distance measurements monitor such surface parameters as: Adhesion, Stiffness, Compliance, Hardness, and Contaminate Thickness. This advanced AFM module is flexible and enables many types of experiments.

Optional Modes

Magnetic Force

Measures surface magnetic field by incorporating a magnetic probe into the AFM. MFM is used to generate images of magnetic fields on a surface, and is particularly useful in the development of magnetic recording technology. Magnetic fields associated with individual magnetic nanoparticles are also revealed through MFM.

Electric force

Electrostatic Force Microscopy (EFM) is a type of dynamic non-contact atomic force Microscope where the electrostatic force is probed. “Dynamic” here means that the cantilever is oscillating and does not make contact with the sample. This force arises due to the attraction or repulsion of separated charges.

Conductive AFM

The C-AFM measures topography and conductivity images simultaneously. This option allows measuring current-voltage (I/V) curves at specific locations on a surface.

Lithography

This NanoLithography software option enables the AFM probe to alter the physical or chemical properties of the surface. Created in LabVIEW and integrated with the AFMControl software. VI’s are available to customers who want to modify the software and create new capabilities.

Scanning Tunneling

In the STM, the current flow between a metal probe and a sample are used to control the distance between the conductive probe and conductive surface. When the probe is scanned across the surface, if the current between the probe and surface are held constant with a feedback control loop driving a piezo ceramic, the topography of the sample’s surface in measured.

Open Liquid Cell

This option includes a special probe holder and open liquid cell for scanning samples submerged in liquids. The Dunk and Scan can directly replace the HR AFM probe holder.

Options

Required Options

When you purchase a HR AFM you must select at least one scanner from the following table:

15

The range of this scanner is 15 microns in X and Y and 7 microns in Z. In a vibration free environment this scanner has a noise floor of <30 picometers. This scanner is recommended for scanning nanostructures.

50

This is the most common scanner selected for use with the HR AFM. It has an XY scan range of 50 microns and a Z range of 17 microns. In a vibration free environment this scanner has noise floor of <40 picometers.

100

For scanning large areas this scanner has an XY range of 100 microns and a Z range of 17 microns. In a vibration free environment this scanner has a noise floor of <50 picometers.

HR-2D Option

Download Data Sheet

The HR-2D is a high resolution AFM with a small footprint dedicated for imaging two-dimensional materials and for use in a glove box. Included with the HR-2D is everything you need to start scanning including a reference sample, probes, data station, and microscope stage.

HR-2D Stage: The dimensions are 7” Wide X 7” Deep X 11” High

Options

XYZ Piezo Scanners

100 um XY, 17 um Z
50 um XY, 17 um Z
15 um XY, 7 um Z

Dunk and Scan Probe Holder

Open liquid cell for scanning samples submerged in liquids. Can directly replace the HR AFM probe holder (not available on HR-2D).

Conductive AFM

Measures the 2D conductivity maps of sample surfaces.

Magnetic Force Microscopy

Measures the surface magnetic field of a sample by incorporating a magnetic probe into the AFM.

Lithography

Uses an AFM probe to alter the physical or chemical property of a sample surface.

Advanced Force Distance Curves

Measures the deflection of a cantilever as it interacts with a surface. Used for measuring adhesion, stiffness, and other molecular forces. Advanced SPIP analysis software needed.

Scanning Tunneling Microscopy

The current flow between the probe and sample is used to control the feedback loop in the microscope when scanning electrically conductive samples.

Electric Force Microscopy

Using two pass scanning, the electric charge at a surface is imaged.

Breakout Box

BNC gives access to most of the signals in the Ebox.

Image Logger

This option allows display of six channels in the forward and reverse direction. It has a spectrum function as well as a twelve channel data logger.

Scanning Kelvin Probe Microscopy (SKPM)

SKPM measures the potential difference between a conductive probe and a conductive sample.

Direct Drive Option

In the HR AFM with direct drive option, three motors are used move the plate that supports the light lever force sensor with a fourth motor controlling the focus of the top view optical microscope. This allows a completely vertical probe approach and keeps the top view microscope focused on the probe.

Motor 1-3

Direct drive tip approach and probe-sample angle control.

Motor 4

Top view optical microscope focus control.

In the direct drive option, motor 1, 2, and 3 simultaneously move the Light lever plate up and down, and the motor 4 controls the optics focus.

Specifications

Scanner Specifications

100 X 100 X 17 50 X 50 X 17 15 X 15 X 7
Engineering Specifications
XY Resolution 0.010 nm 0.005 nm 0.003 nm
XY Linearity <0.1% <0.1% <0.1%
Z Resolution 0.003 nm 0.003 nm 0.0015 nm
Z Linearity <0.1% <0.1% <0.1%
Performance Specializations
XY Range 100 µm 50 µm 15 µm
XY Linearity <0.1% <0.1% <0.1%
XY Resolution
Closed Loop <6 nm <3 nm <1 nm
Open Loop <1 nm <1 nm <0.3 nm
Z Range 17 µm 17 µm 7 µm
Z Linearity
Open Loop <5% <5% <5%
Closed Loop <1% <1% <1%
Z Sensor Noise 1 nm 1 nm N.A.
Z Feedback Noise <0.15 nm <0.15 nm <0.35 nm
Actuator Type Piezo Piezo Piezo
Design Modified Tripod Modified Tripod Modified Tripod
XY Sensor Type Strain Gauge Strain Gauge Strain Gauge
Z Sensor Type Strain Gauge Strain Gauge N.A.

Electronic Control Specifications

XY Scan 2 X 28-bits 24-bit Scan DAC, 4-bit gain 192 Khz
XY Linearization Control 2 X 24-bits 0.005 nm 192 Khz
Z Axis Control Analog 4 amplifier – GPID 1 microvolt noise
Input Signal Bandwidth 5 Mhz
Z axis Signal Capture 20 bits 16-bit ADC, 4-bit gain 50 Khz
Phase Signal Capture 2 X 16 bits ADC 50 Khz
L-R Signal Capture 2 X 16 bits ADC 50 Khz
Amplitude Signal Capture 2 X 16 bits ADC 50 Khz
Z Error Signal Capture 2 X 16 bits ADC 50 Khz
Main Controller MPU 80 Mz/105 DMIPS, 32 Bits (5-stage pipeline, Harvard architecture)
Excitation/Modulation Analog PLL 0-800 Khz
Communication USB 2.0
Signal capture specified includes the image logger option. Without Image Logger 1 X 16 bits

Optional Electronics Specifications

User Input Signal (1) 32 X 18 bits ADC 625 Khz
User Output (1) 32 X 18 bits DAC 625 Khz
User Monitor (1) 48 Lines Digital IO Mhz
Optional Controller MPU (2) 80 Mz/105 DMIPS, 32 Bits (5-stage pipeline, Harvard architecture)

(1) Optional User I/O upgrade
(2) Used for MFM, PhotoCorrect, EFM

Software

Environment LabVIEW
Operating System Windows
Image Acquisition Real Time Display (2 of 8 channels)
Control Parameters
PID Yes
Setpoint Yes
Range Yes
Scan Rate Yes
Image Rotate 0 and 90 degrees
Laser Align Yes
Vibrating Freq. Display Yes
Force Distance Yes
Tip Approach Yes
Oscilloscope Yes
Image Store Format Industry Standard
Image Pixels 16 X 16 to 1024 X 1024
H.V. Gain Control XY and Z
Real Time Display Line Level, Light Shaded, Grey Color Pallet
Calibration System Window
Probe Center Yes
Video Microscope
Minimum Zoom Maximum Zoom
Field of view 2 x 2 mm 300 x 300 μm
Resolution 20 μm 2 μm
Working Distance 114 mm 114 mm
Magnification 45X 400X
Top View Optic

  • Research Grade 45-400x

  • Mechanical 7:1 Zoom ratio
  • 5 MegaPixel CMOS Camera
  • 114 mm working distance

  • Coaxial LED illumination

Side View Optic
  • Cell Phone Type

  • LED illumination

  • 2 MegaPixel CMOS camera

* Z Noise performance depends greatly on the environment the HR AFM is used in. Best Z noise performance is obtained in a vibration-free environment.

** Every effort is made to present accurate specifications, however, due to circumstances beyond AFMWorkshop’s control specifications are subject to change. All specifications are accurate to +/-5%.