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Educational Atomic Force Microscope (AFM)![]()
Breadboard Not Included ![]() Please Wait Educational Atomic Force Microscope
![]() Click to Enlarge The laser beam collimation in the EDU-AFM1(/M) Education Kit is being adjusted. Experiment
Thorlabs' Educational Atomic Force Microscope (AFM) includes all of the components* needed for students to build a basic atomic force microscope in the lab. This teaching system allows students to handle and adjust the setup while performing experiments to image one of the included samples. While not a research grade instrument, the system can achieve sufficient resolution to demonstrate the physical properties of and technology used in AFMs. It is capable of imaging in constant height, constant force, and lateral force mode, as well as recording force-distance curves. In addition to the microscope components, the educational kit includes:
Together, these features make Thorlabs' educational atomic force microscope a broad-based, application-oriented setup that is an ideal introduction for advanced undergraduate students. *The AFM must be mounted on an optical table or breadboard, which is not included in this kit. If your lab does not already have a suitable one, we recommend using the B1824F Nexus® Honeycomb Breadboard with the AV5 Damping Feet for the imperial kits (B4560A with AV5/M, respectively, for metric kits), which are available for purchase separately below. Do not use a standard aluminum breadboard, as it will not sufficiently isolate the AFM from vibrations. Thorlabs Educational ProductsThorlabs' line of educational products aims to promote physics, optics, and photonics by covering many classic experiments, as well as emerging fields of research. Each educational kit includes all the necessary components and a manual that contains both detailed setup instructions and extensive teaching materials. These lab kits are being offered at the price of the included components, with the educational materials offered for free. Technical support from our educational team is available both before and after purchase. Purchasing Note: English and German language manuals/teaching information are available for this product. The imperial kit contains the English manual and US-style power cord. The appropriate manual and power cord will be included in the metric kit based on your shipping location. The power supplies and other electronic devices in both the metric and the imperial kit accept voltages of 230 VAC and 120 VAC. Some power supplies include a switch for selecting the mains voltage. See the respective manuals for details. Please contact Tech Support if you need a different language, cord style, or power supply. As with all products on our website, taxes are not included in the price shown below. ![]() A Schematic of the EDU-AFM1(/M) Educational Atomic Force Microscope. The red lines represent the path of the laser light and the blue lines represent electrical connections. Thorlabs demonstration/educational atomic force microscope (AFM) kit is designed for classroom, lab, and other educational uses. It features an AFM probe, a sample holder on a motorized stage with motorized closed-loop positioning control, a laser and four-segment photodiode detector for measuring the probe deflection, and the intuitive EDU-AFM software package to control the setup. Operation Sample Stage and Cantilever ![]() Click to Enlarge Laser Collimation (Top Right), Cantilever (Center), and Detector Mount (Top Left) Assemblies Image Acquisition and Measurement Modes ![]() Ideas for Modifying the Kit?We strongly encourage users to make their own modifications to our kits to enhance or expand the kits' capabilities, including adding or altering components. If you would like to share your modifications with the community, let us know and we will add your ideas with a reference to the kit webpage. In Constant Force Mode, the system is set up to keep the cantilever deflection constant: this is accomplished by setting up a closed feedback loop between the photodiode, the DSP in the auto aligner, and the Z-axis piezo controller. When the four segment photodiode detects a change in the laser spot position, the DSP in the auto aligner calculates the adjustment to the sample height needed to maintain the initial cantilever deflection. This signal is used by the EDU-AFM software as height information, combined with the data from the X- and Y-axis piezo controllers, to create a contour map of the sample surface. In addition to these two scanning modes, the EDU-AFM1(/M) can also measure the lateral forces on the cantilever and the way forces on the cantilever change as the sample surface is approached. For more information on AFM scanning modes, see the AFM Basics tab. Laser Safety Information
![]() Click to Enlarge This image was taken with the digital microscope included in the AFM kit and shows the laser focused on the cantilever. What is Atomic Force Microscopy?Atomic force microscopy, a form of scanning probe microscopy, offers fascinating insights into structures beyond the resolution limits of optical microscopy and therefore into the world of nanostructures. The scanning method is based on a fine scanning probe, which consists of a flexible arm called a cantilever that supports a tip radius less than 10 nm. As the tip interacts with the surface of a sample, the deflection of the cantilever is recorded in order to create an elevation profile of the surface line by line. For an atomic force microscope (AFM) to function properly, the cantilever must meet several requirements. A low spring constant is needed so that small forces can be measured. It must have a large resonance frequency to minimize the influence of mechanical oscillations. Therefore, the cantilever must both have low mass and a small size. In the EDU-AFM1(/M), the light from a laser source is focused onto the cantilever by a focusing lens in an adjustable zoom housing. The light reflected from the cantilever strikes a position-sensing detector (four-segment photodiode). When the cantilever is deflected during scanning due to a change in the surface height, the corresponding deflection of the laser beam is measured, and then read and processed by the digital signal processor (DSP). Depending on the scanning mode used (detailed below), the deflection-dependent voltages from the four-segment photodiode can be used as height information to create a contour map of the sample surface or as a feedback signal between the DSP and a z-axis positioning unit supporting the sample. In the latter case, the Z-axis positioning unit can be used to adjust the height of the sample to maintain a constant cantilever deflection (as measured by the four segment photodiode), and a contour map the sample surface is created by recording the changes in the stage height. Measurement ModesAll AFM scanning modes are based on the interaction between the probe tip and the sample, but different aspects of this interaction can be probed when examining a sample. In general, AFM modes can be divided into two categories. In contact scanning modes, the cantilever tip is dragged across the surface of the sample and the effects on the deflection of the cantilever are measured. In dynamic scanning modes, the tip of the cantilever is forced to oscillate and the effects of this oscillation are measured. The EDU-AFM1(/M) is only capable scanning in a contact mode, so we will focus on the two types of contact modes here: constant height mode and constant force mode. ![]() Figure 2: In Constant Force Mode, the cantilever deflection remains constant and the movement of the probe holder (or sample) needed to maintain that deflection is measured. ![]() Figure 1: In Constant Height Mode, the sample height remains constant and the cantilever deflection is measured. Constant Height Constant Force ![]() Figure 3: In lateral force mode, the torsion of the cantilever is measured instead of the deflection. The tip torsion will behave differently than the deflection for changes in sample surface height and changes in the sample surface material. Lateral Force Measurement (LFM) Force-Distance Curves As the sample is moved towards the probe, there will be a point where attractive forces cause the tip to engage with the sample (Snap-In). The sample continues to move towards the probe until the cantilever straightens, and is then deflected upward. Then, the sample is moved downwards again. The probe tip will remain engaged with the sample surface until the restoring spring force of the cantilever is greater than the adhesive forces between the tip and the sample, at which point the cantilever will return to its rest position (Pull-Off). Note that the height of the sample at Snap-In and Pull-Off are not the same. ![]() Figure 4: This schematic illustrates how the cantilever deformation changes during a Force-Distance Measurement. The red arrows indicate the motion of the sample relative to the probe holder, while the blue arrows indicate the motion of the cantilever. The green arrows indicate the difference in sample height between when the cantilever first engages with the sample (Snap-In) and when the cantilever disengages with the sample (Pull-Off). ![]() Click to Enlarge Screenshot of the Gwyddion Software During the XY Calibration Procedure After students construct the educational AFM, they can complete a series of exercises outlined in the manual to practice different scanning methods and familiarize themselves with post-processing techniques in Gwyddion (see the Software tab). This tab includes a brief summary of the experiments included with the EDU-AFM1(/M) kit, with exercise numbers that match the manual. Lateral Calibration using the Included MicrostructureThe AFM can be calibrated using the included microstructure to enhance the measurement accuracy. Through this set of exercises, students learn how to check or redo the calibration. Lateral calibration allows for the instrument to accurately record the location of each data point in X and Y. The microstructure sample is designed specifically for this purpose with 100 nm tall features that are arranged with a pitch that varies between 5 µm and 10 µm. Exercise 1.1: Measure the circle structure of the microstructure sample in a 20 µm x 20 µm scanning window in constant force mode with the default calibration settings. Measure the same image with strain gauge feedback enabled and disabled. Exercise 1.2: Use the Gwyddion software to determine the structure pitch in the X and Y directions, and calculate the feature size compared to the datasheet information in %. Exercise 1.3: Enter the calibration data from Exercise 1.2 into the EDU-AFM software, and record the same image again to check the calibration results. ![]() Click to Enlarge This image of a CD was taken with the EDU-AFM1. The pit length (red line), pit width (blue line), and track width (green line) are marked. Topography of CD, DVD, and Blu-Ray DiscsThis kit includes CD, DVD, and Blu-Ray disc samples that were taken out of the production process prior to encapsulation. This means that the stamped surface is accessible and ready for a surface scan. Students can image each type of disc, measure the surface features, and compare the data densities of the different encoding methods Exercise 2.1: Record an image of the CD surface in constant force mode. Exercise 2.2: Record an image of the DVD in constant force mode. Exercise 2.3: Record an image of the Blu-Ray disc in constant force mode. Exercise 2.4: Determine the track width, track pitch, minimum and maximum pit length of the CD, DVD and Blu-Ray disc. Exercise 2.5: Determine the pit depth using the profile function in Gwyddion. Compare the pit depths of the CD, DVD and Blu-ray samples and explain why they are different. Exercise 2.6: Calculate the maximum storage capacity of a CD. Lateral Force MeasurementStudents practice taking lateral force measurements with the AFM using the included microstructure sample and a human hair. Exercise 3.1: Scan the microstructure sample in constant height mode, recording a lateral force image in a 20 µm x 20 µm scan area. Interpret the profile information. Exercise 3.2.1: Record the topography of a human hair. Scan the hair in constant force mode. Exercise 3.2.2: Record a lateral force image of a hair in constant height mode. ![]() Click to Enlarge A screenshot from the EDU-AFM software showing a force-distance measurement. The key features of the curve have been labeled. Force-Distance MeasurementThis series of exercises familiarizes students with force-distance measurements. These measurements can be used to determine the adhesion force between the tip and the sample surface, as well as the modulus of elasticity. The cantilever spring constant can also be calculated. Exercise 4.1: Record a force-distance curve (without zoom) of the microstructure sample and determine the rest position, snap-in, and pull-off. What effects are observable? Exercise 5.1: Determine the spring constant of the cantilever. Exercise 6.1: Measure the force-distance curve of various samples (for example: stainless steel, plastic or rubber). Label the most interesting points of a force-distance curve. Exercise 6.2: Determine the maximum adhesion force. Exercise 7.1: Compare the deflection of the cantilever with a hard (non-deformable) sample to the sample for which you want to estimate the modulus of elasticity. Exercise 7.2: From Exercise 7.1, determine the depth of the cantilever deflection compared to the reference sample and use this to estimate Young's modulus of elasticity. Atomic Force Microscope Kit ComponentsThe EDU-AFM1(/M) must be mounted on an optical table or breadboard. As these are common in many labs, we have not included a breadboard in this kit. If you need to purchase a breadboard separately, we recommend the B1824F Nexus® Honeycomb Breadboard with the AV5 Damping Feet for the imperial kits (B4560A with AV5/M, respectively, for metric kits), which are available separately below. Thorlabs' Atomic Force Microscope Kits are available in imperial and metric versions. In cases where the metric and imperial kits contain parts with different item numbers, metric part numbers and measurements are indicated by parentheses unless otherwise noted.
Imperial Kit: Included Hardware and Screws
Metric Kit: Included Hardware and Screws
SoftwareEach kit includes a USB stick with the free EDU-AFM software package, used to control the AFM and record measurements. The software features a graphical representation of the Four Segment Photodetector, as well as separate tabs for each measuring mode. Measurements can be saved as an image or in data format. If the original USB stick is lost, please contact Tech Support for another copy of the software. Future software updates will be made available for free, and can be accessed through the EDU-AFM's Software Update function. Gwyddion ![]() Click to Enlarge A graphical representation of the four segment photodiode in the EDU-AFM software. The voltage produced by the four-segment photodiode by the laser total intensity (SUM) and the laser position (XDIFF/YDIFF) appear in the upper right hand corner of the graph. The XY position of the stage, as well as the feedback from the strain gauge and z-axis controller, appear in the side bar. ![]() Click to Enlarge An example measurement of the microstructure sample in Constant Height Mode. ![]() Click to Enlarge An example of a force-distance curve. The stage moves upwards by 4 µm (15 V), and the cantilever deflection as it interacts with the sample is measured. This data can be used to calculate the adhesion forces and Young's modulus of the material. Assembly of the EDU-AFM1(/M) kit. The breadboard is not included, but can be purchased separately below.
Kit AssemblyThe video to the right shows the steps for assembling the EDU-AFM1(/M) kit. The video speed can be adjusted by clicking on the gear icon in the lower right-hand corner of the player. A mechanical drawing and 3D models of the setup in the video are provided through the links to the right. Please note that while the drawings and solid models show a breadboard, one is not included in the kit as breadboards and optical tables are a staple in many labs. A B1824F Nexus® Honeycomb Breadboard for the imperial kit or B4560A Nexus® Honeycomb Breadboard for the metric kit can be purchased separately below; a standard aluminum breadboard should not be used with the kit as it will not sufficiently isolate the AFM from vibrations.
Tip Engagement on a Sample Using Constant Force Mode
![]() Click to Enlarge 2D Image Taken with EDU-AFM Software Tip Engagement of the AFM KitThe video to the right shows how a sample can be manually adjusted to engage the tip of the AFM probe. Differential screws with both coarse and fine adjustment are used in combination with a height feedback sensor for gentle contact that does not damage the tip of the probe. The camera has high magnification so that the sub-millimeter thick tip can be seen in the software during its approach to the sample. Once the sample is engaged with the tip, the video shows the AFM kit scanning in constant force mode. Note that the USB camera is capable of showing the scanning movement of the cantilever. An example image is shown to the right. For more example images, please see the Image Gallery tab. Changing the Cantilever Tip ![]() Click to Enlarge This image was taken with the digital microscope included in the AFM kit and shows the laser focused on the cantilever. Changing the AFM ProbeOver time, the tip of the AFM probe will wear, eventually leading to a tip diameter that is larger than the expected features or image artifacts. When this happens, the probe should be changed, as demonstrated in the video to the right. The EDU-AFM1(/M) kit includes 10 BudgetSensors *BudgetSensors cantilevers can be found here. Educational Atomic Force Microscope Image GalleryThe images below were all taken using Thorlabs' Educational Atomic Force Microscope (AFM). Of the samples shown below, the microstructure sample and blu-ray disc are included with the kit. If you would like to share your own AFM images, you can submit them to techsupport@thorlabs.com and we'll consider them for addition to the image gallery.
BudgetSensors HS100-MG Microstructure (Included with Kit)![]() Click to Enlarge 2D Image Taken with EDU-AFM Software ![]() Click to Enlarge 3D View Generated by Post Processing in Gwyddion Image of the BudgetSensors HS-100MG Microstructure included with the EDU-AFM1(/M) kit. Blu-Ray Disc (Included with Kit)![]() Click to Enlarge 2D Image taken with EDU-AFM1(/M) ![]() Click to Enlarge 3D View Generated by Post Processing in Gwyddion Image of the Blu-Ray Sample (Open Layer) included with the EDU-AFM1(/M) kit. AFM Stripe Artifacts![]() Click to Enlarge 2D Image of Microstructure ![]() Click to Enlarge 2D Image of CD These images show examples of stripe artifacts caused by dust pushed over the surface of the microstructure sample by the probe tip (left) and the soft sample surface of the stamped CD structure (right). Moth Eye Cones![]() Click to Enlarge 2D Image taken with EDU-AFM1(/M) ![]() Click to Enlarge 3D View Generated by Post Processing in Gwyddion Image of Moth Eye Cones Dried Blood Cell![]() Click to Enlarge 2D Image taken with EDU-AFM1(/M) ![]() Click to Enlarge 3D View Generated by Post Processing in Gwyddion with Colorized Overlay Image of a Dried Blood Cell Human Hair![]() Click to Enlarge 2D Image taken with EDU-AFM1(/M) ![]() Click to Enlarge 3D View Generated by Post Processing in Gwyddion Image of a Human Hair Cobalt Nanoparticles![]() Click to Enlarge 2D Image taken with EDU-AFM1(/M) ![]() Click to Enlarge 3D View Generated by Post Processing in Gwyddion As an example, the Educational AFM Kit was used to image a PELCO® AFM Tip and Resolution Test Specimen, which consists of a single layer of cobalt particles. The particles are flattened half-spheres with a radius typically larger than the height and particles heights varying between 1 and 5 nm. When imaged with the EDU-AFM1, the measured particle size was approximately 25 nm in diameter. The tip diameter is approximately 15 nm, which results in a resolved particle size of 10 nm. Further information can be found in the manual.
User Images: Courtesy of Richard Becher (KIT)These images, taken using the Educational AFM, were provided to Thorlabs by Richard Becher from the Karlsruhe Institute of Technology (KIT). Gore-Tex®![]() Click to Enlarge 2D Image Taken with EDU-AFM Software ![]() Click to Enlarge 3D View Generated by Post Processing in Gwyddion The pores in Gore-Tex® material are smaller than 1 µm, making them too small for water drops to pass through. Vapor can pass through the other side of the fabric, making this material both breathable and waterproof. Structures to Enhance Solar Cell Light Absorption![]() Click to Enlarge 2D Image taken with EDU-AFM1(/M) The geometrical structure of rose petal skins enhances their light-absorbing capabilities. Scientists at KIT have applied materials molded to match this structure to the surface of solar cells, enhancing their light gathering capabilities. The images above are of one such structure. Sample courtesy of the Light Technology Institute at KIT Karlsruhe (www.lti.kit.edu). Synthetic Moth Eye Structures![]() Click to Enlarge 2D Image taken with EDU-AFM1(/M) ![]() Click to Enlarge 3D View Generated by Post Processing in Gwyddion Moth eyes are covered in an array of light sensitive cones that reduce reflections at the air-chitin border. Materials with an array of cones that are the same size as those in a real moth eye are used in technology to make surfaces antireflective. Sample courtesy of temicon® (www.temicon.com). Irridescent Butterfly Wing![]() Click to Enlarge 2D Image taken with EDU-AFM1(/M) The cascading nanostructures found on the wings of the Morpho Aega butterfly are responsible for its irridescent color. This sample is courtesy of Naturkundemuseum Karlsruhe (www.smnk.de).
Have you or your class taken an image with the EDU-AFM1(/M) that you would like to share? If so, e-mail your photos to us at techsupport@thorlabs.com and we'll consider them for addition to the image gallery.Laser Safety and ClassificationSafe practices and proper usage of safety equipment should be taken into consideration when operating lasers. The eye is susceptible to injury, even from very low levels of laser light. Thorlabs offers a range of laser safety accessories that can be used to reduce the risk of accidents or injuries. Laser emission in the visible and near infrared spectral ranges has the greatest potential for retinal injury, as the cornea and lens are transparent to those wavelengths, and the lens can focus the laser energy onto the retina. Safe Practices and Light Safety Accessories
Laser ClassificationLasers are categorized into different classes according to their ability to cause eye and other damage. The International Electrotechnical Commission (IEC) is a global organization that prepares and publishes international standards for all electrical, electronic, and related technologies. The IEC document 60825-1 outlines the safety of laser products. A description of each class of laser is given below:
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The AFM in our EDU-AFM1(/M) kit must be mounted on an optical table or breadboard. As these are common in many labs, we have not included a breadboard in this kit. If you need to purchase a breadboard separately, we recommend the B1824F Nexus Honeycomb Breadboard with the AV5 Damping Feet for the imperial kit or the B4560A Nexus Honeycomb Breadboard with AV5/M Damping Feet for the metric kit, available here. Do not use a standard aluminum breadboard, as it will not sufficiently isolate the setup from vibrations. | ||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
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