Operating Instructions easyScan 2 AFM Version 1.
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Table of contents The easyScan 2 AFM 7 Features.................................................................................................8 easyScan 2 Controller 8 AFM Measurement 10 Components of the System .................................................................12 Contents of the Tool set 14 Connectors, Indicators and Controls ...................................................15 The Scan head 15 The Controller 16 Installing the easyScan 2 AFM 18 Installing the Hardware ...............
2. Manual approach using the approach stage 40 3. Automatic final approach 41 Starting a measurement ......................................................................43 Selecting a measurement area............................................................44 Storing the measurement ....................................................................46 Creating a report..................................................................................46 Finishing ........................................
TABLE OF CONTENTS About this Manual This manual gives instructions on how to set up and use your Nanosurf easyScan 2 AFM system. Installing the easyScan 2 AFM should be read when installing your easyScan 2 AFM system. The chapters Preparing for Measurement and A First Measurement should be read by all users, because they contain useful instructions for everyday measurements. The other chapters give more information for advanced or interested users.
The easyScan 2 AFM The Nanosurf easyScan 2 AFM is an atomic force microscope system that can make nanometer scale resolution measurements of topography and several other properties of a sample. The easyScan 2 AFM system is a modular scanning probe system that can be upgraded to obtain more measurement capabilities. The main parts of the basic system are the easyScan 2 AFM scan head, the AFM Sample stage, the easyScan 2 Controller with AFM Basic module, and the easyScan 2 software.
THE EASYSCAN 2 AFM Features easyScan 2 Controller Electronics Electronics size / weight Power supply Computer interface Integrated USB hub Measurement channels 470 x 120 x 80mm / 2.4kg 90 - 240V~/ 30W 50/60Hz USB 1.1 2 Ports (100mA max) 16bit A/D converters, up to seven signals depending on mode.
FEATURES Computer requirements Operating system Electronics interface Recommended PC hardware Windows 2000, XP or newer USB port Pentium 4/M or AMD Athlon, 256MB RAM, True color 1024x786 video card, HW Open GL accelerator Computer not included with system.
THE EASYSCAN 2 AFM Additional analog user inputs 2x 16bit A/D converters, ±10V Additional modes Almost unlimited User inputs can optionally be measured in all Imaging and Spectroscopy modes. User outputs can be modulated in Spectroscopy measurements. AFM Measurement AFM Scan Head: range 1) Maximum Scan Maximum Z-range Drive resolution Z 2) 10µm 10µm 70µm 70µm 110µm 110µm 2µm 0.027nm 14µm 0.21nm 22µm 0.34nm 0.15nm 1.1nm 1.7nm Drive resolution XY 2) XY-Linearity Mean Error <0.6% <1.2% <0.
FEATURES View field Sample illumination Top 4x4mm / side 5x3mm White LEDs (brightness 0-100%) Compatible cantilevers Manufacturers Static modes Dynamic modes Spreading Resistance mode Available tips Typical static load Typical dynamic frequency NanoSensors® and NanoWorld® (www.nanoworld.
THE EASYSCAN 2 AFM Additional spectroscopy Phase-Distance, Current-Voltage, Currentmodes Distance etc. Phase contrast range ± 90° Phase contrast resolution < 0.05° Phase reference range 0 - 360° Tip current measurement ± 100µA, 3nA resolution Both the AFM Basic Module and the AFM Dynamic Module are required for using the AFM Mode Extension Module. AFM Video Module Camera system Magnification View field Image pixels Video display Analog video output Dual video (top/side view) Top 100x / side 70x Top 3.
COMPONENTS OF THE SYSTEM 1 4 2 5 3 7 6 18 12 13 17 19 Components: The easyScan 2 AFM system 2. USB cable 3. Mains cable 4. easyScan 2 AFM Scan head(s) with AFM Video Camera (with AFM Video Module) 5. Scan head case 6. Scan head cable 7. Video Camera cable (with AFM Video Module) 8. AFM calibration certificate 9. This easyScan 2 AFM Operating Instructions manual 10. easyScan 2 Software Reference manual 11.
THE EASYSCAN 2 AFM 13. AFM Sample Stage (option) 14. Micrometre Translation Stage (option) 15. User's Guide; Translation Stage, Model: 9064 (with Micrometre Translation Stage) 16. Positioning Tool Set (with Micrometre Translation Stage) 17. Break-out cable (with Signal Module: S) 18. Connector box (with Signal Module: A) 19. Signal Module cables (2x) (with Signal Module: A) 20. Scripting Interface Certificate of purchase with Activation key printed on it (with Scripting Interface) 21.
CONNECTORS, INDICATORS AND CONTROLS 4. Screwdriver, 2.3 mm 5. Cantilever insertion tool (usually mounted in DropStop 6. DropStop) 7. Sample holder (with AFM Sample Stage) 8. AFM Basic Sample Kit (option) with CD-ROM Sample, Microstructure sample 9. AFM Calibration Samples Kit (option) with Calibration grid: 10 µm/ 100nm, Calibration grid: 660nm, Flatness sample 10. Set of 10 CONTR cantilevers (option) 11. Set of 10 NCLR cantilevers (option) 12.
THE EASYSCAN 2 AFM The Controller Module lights Scan Head lights Probe Status light Video Out connector Video In (optional) connector (optional) Signal Out connector (optional) Signal In connector (optional) Scan head cable connector Controller Serial number Power switch S/N: 23-05-001 USB outputs (to dongle) USB active light Mains power connector USB input (from PC) USB power light The easyScan 2 Controller Status lights All status lights on top of the Controller will light up for one second
CONNECTORS, INDICATORS AND CONTROLS point for some time. The tip is probably not in contact with the sample surface. green The scanner is not in a limit position, and the feedback loop can measure the sample surface. blinking green The feedback loop has been turned off in the software. blinking red There is no signal with which to do feedback: The light intensity on the photodetector of the laser beam deflection system is too low. Refer to section Probe Status light blinks red (p.
INSTALLING THE EASYSCAN 2 AFM Installing the easyScan 2 AFM The following sections describe the installation of the easyScan 2 AFM. Important! To make high quality measurements, the following precautions must be taken to keep equipment clean: • Never touch the cantilever tips, the cantilevers (figure Contents of the AFM Tool set (p.14), 10, 11), or the open part of the Scan head (figure Cantilever deflection detection system (p.29)).
INSTALLING THE HARDWARE It is recommended to cover the instrument with a box to shield it from near infrared light from artificial light sources, because this light may cause noise in the cantilever deflection detection system. If the vibration isolation of your table is insufficient for your measurement purposes, an optional active vibration isolation table is available.
INSTALLING THE EASYSCAN 2 AFM Installing the AFM Video Module - Connect the Video Camera cable to the connector on the AFM Video Camera (Components, 4) and the Video In connector on the Controller (figure The easyScan 2 Controller (p.16)). In case of an upgrade, both the scan head and the Controller must be sent in to your local Nanosurf distributor for mounting the Video Camera on the Scan Head and installing the Video Camera electronics in the Controller.
STORING THE INSTRUMENT Warning! This product contains a Class 1 Laser Invisible laser radiation! The laser is located behind the cantilever. Although the optical power should do no damage when the instrument is assembled, avoid looking directly into the laser beam. Laser source information: Wavelength: 830nm Optical power: <0.4mW Class one Laser First all status lights on top of the Controller briefly light up.
INSTALLING THE EASYSCAN 2 AFM Packing: The easyScan 2 AFM system packed in the Instrument Case Installing the Software - Check that the computer on which you want to install the software fulfils the requirements listed in section Computer requirements (p.9). - Disconnect the USB cable from the Controller. - Turn on your computer and start Windows. Important! Make sure you have administrator privileges before software installation. Do not run any other program while installing the scan software.
INSTALLING THE SOFTWARE The setup program should start automatically. If this does not happen, proceed as follows: - Open the easyScan 2 Installation CD. - Start the program ‘StartCDMenu.exe’. - Click ‘Full Installation of Nanosurf easyScan 2’. The installation program will now start installing all components of the Nanosurf easyScan 2 AFM: The hardware drivers, the easyScan 2 software, DirectX 9. - Follow the instructions given by the setup program.
INSTALLING THE EASYSCAN 2 AFM - Choose ‘Automatic installation’. - Click the default choice in all dialogs. The USB High Speed Serial Converter is now installed. USB Serial Port When the operating system finds the ‘USB Serial Port’, it asks what to do: - Select ‘Automatic installation’. - Click the default choice in all dialogs. The USB Serial Port is now installed. USB Video Adapter The USB Video Adapter driver is only installed if the Controller contains a Video Module.
INSTALLING THE SOFTWARE Important! The easyScan 2 AFM Installation CD contains calibration information (.hed files) specific to your instrument, therefore you should keep (a backup copy of) the CD delivered with the instrument. Step 3 - Installation of DirectX 9 The easyScan 2 software needs DirectX 9 or newer for correct operation. Click the default choice in all dialogs. - After installing DirectX 9, the computer may have to re-boot.
INSTALLING THE EASYSCAN 2 AFM The red USB power light on the Controller should now light up, and the PC should now automatically detect the ‘USB Device’, and asks what to do to install the ‘USB Video Adapter’. On some computers, the detection and installation process may take some time (20 seconds or more), please be patient. - Select ‘Automatic installation’. During installation of the video adapter under windows XP, windows may notify you that the driver is not digitally signed.
INITIALISING THE CONTROLLER Preparing for Measurement This chapter describes actions that you perform on a day-to-day basis as a preparation for your measurements, when the instrument has already been set up according to the instructions in chapter Installing the easyScan 2 AFM (p.18). These steps are changing the cantilever, selecting a sample stage, and preparing the sample.
PREPARING FOR MEASUREMENT Installing the cantilever To maximise ease of use, the Nanosurf easyScan 2 AFM is designed so that the cantilever can be installed and removed without having to readjust the cantilever deflection detection system. This is possible because an alignment system is used that consists of an alignment chip and matching grooves in the back side of the cantilever chip. This positions the cantilever with micrometer accuracy (see figure Cantilever, left).
INSTALLING THE CANTILEVER Sample illumination Cantilever Photodetector Cantilever holder spring Laser Alignment chip Hole for cantilever insertion tool Cantilever deflection detection system operating mode; the more flexible, long CONTR cantilever is generally used for the static operating mode. When you change to a different cantilever type: - Select the cantilever type using the ‘Mounted cantilever’ drop-down menu in the Operating mode panel.
PREPARING FOR MEASUREMENT - Turn the scan-head upside-down. - Close the DropStop (figure Closing the DropStop). Closing the DropStop The laser beam is now blocked by the DropStop. As a consequence, the Probe Status light on the easyScan 2 Controller will now blink red. - Place the cantilever insertion tool (figure Contents of the AFM Tool set (p.14), 5) into the hole behind the alignment chip (figure Mounting the cantilever, top left). The Cantilever Holder Spring opens.
INSTALLING THE CANTILEVER Mounting the cantilever: top left: Inserting the cantilever insertion tool; top right: Inserting/ Removing the cantilever; bottom right: Correctly inserted cantilever Cantilever Alignment: left: Correct, the mirrored environment light shows a pattern that is continuous on the cantilever and the alignment chip; centre, right: Incorrect, the mirrored environment light shows a different pattern on the cantilever than on the alignment chip. - Remove the DropStop.
PREPARING FOR MEASUREMENT Installing the sample Preparing the Sample The easyScan 2 AFM can be used to examine any material with a surface roughness that does not exceed the height range of the scanning tip. Nevertheless the choice and preparation of the surface can influence the surfacetip interaction. Examples of influencing factors are excess moisture, dust, grease etc. Because of this some of the samples need special preparation to clean their surface. Generally, clean as little as possible.
INSTALLING THE SAMPLE Calibration Sample Kit The samples supplied in the optional Calibration Sample kit are meant as test samples that can also be used to check the correctness of the instrument’s calibration. Certified Calibration grids are available as an option. The Calibration grid: 10 µm/100 nm can be used for testing the xy-calibration of the 70µm and 100µm scanners and for testing z-calibration.
PREPARING FOR MEASUREMENT mounted on the sample stage. You can either put the sample directly on the sample stage, or mount it on the sample holder (figure Contents of the AFM Tool set (p.14), 6). Scan head on the Sample Stage Mounting a sample onto the sample holder The simplest way to do this is to use put the sample on the sticky side of a Post-it® note that is attached to the sample holder using double sided adhesive tape.
INSTALLING THE SAMPLE Important! Avoid all mechanical impact on the cantilever when placing the sample holder under the Scan head. Any impact will damage the tip.
A FIRST MEASUREMENT A First Measurement In this chapter, step by step instructions are given as to how to operate the microscope and make a simple measurement. More detailed explanations of the software and the system are given in the Software Reference manual.
PREPARING THE INSTRUMENT Preparing the instrument Important! • Never touch the cantilever or the surface of the sample! Good results rely heavily on a correct treatment of the tip and the sample. • Avoid exposing the system to direct light while measuring. This could influence the beam deflection detector and reduce the quality of the measurement. Prepare the instrument as follows (see chapter Preparing for Measurement (p.
A FIRST MEASUREMENT ing it with the Tab key. • The value of an activated parameter can be increased and decreased using the up and down arrow keys on the keyboard. The new value is automatically used after one second. • The value of a numerical parameter can also be increased and decreased by clicking the arrow buttons with the mouse pointer. The new value is automatically used after one second. • The value of an active numerical parameter can also be entered using the keyboard.
APPROACHING THE SAMPLE Approaching the sample To start measuring, the tip must come within a fraction of a nanometer of the sample without touching it with too much force. To achieve this, a very careful and sensitive approach of the cantilever is required. This delicate operation is carried out in three steps: Manual coarse approach, manual approach using the approach stage, and the automatic final approach.
A FIRST MEASUREMENT The side view should look like figure Side view of the cantilever after manual coarse approach. You can use the cantilever as a ruler to judge distances in the views of the integrated optics. Side view of the cantilever after manual coarse approach 1. Manual Coarse approach In this step, the sample surface is brought within the range of the fine approach stage. - Use the three levelling screws (figure Parts of the scan head (p.
APPROACHING THE SAMPLE grated optics. The tip should not come closer to the sample than a few times the cantilever width. (figure View of the cantilever after manual approach, left). View of the cantilever after manual approach: left: side view, right: top view - Whilst observing the tip sample distance, click and hold the tip is close enough to the sample. until The sample should now be in focus. Now use the top view image to find a suitable location to measure on.
A FIRST MEASUREMENT - If you are operating in Static Force mode, select a CONTR type cantilever. In dynamic mode, the instrument will automatically determine the vibration frequency used in the dynamic mode. To do this, it uses a measurement of the cantilever vibration amplitude as a function of excitation frequency. This measurement is not displayed when using the default settings. Nevertheless, it is instructive to see this measurement at least once.
STARTING A MEASUREMENT - Select the ‘Easy level’ user interface mode. Now check that the set point and the feedback speed are set properly: - Click in the Navigator to open the Z-Controller panel. For Dynamic Force mode: - Set ‘Set point’ to 50-70%. For Static Force mode: - Set ‘Set point’ to 10-20nN. - Set ‘Loop gain’ to 1000-1500. Now you can start the approach: - Click in the Approach panel. The cantilever is moved towards the sample using the approach stage, with the Z-Controller turned on.
A FIRST MEASUREMENT Reminder: Measurements on the micrometer/nanometer scale are very sensitive. Direct light, fast movements causing air flow and temperature variations near the Scan head can influence and disturb the measurement. When the measurement contains large disturbances, or no two scan lines are similar, stop measuring and reduce or eliminate the disturbances: - Click and follow the instructions of the chapter Problems and Solutions (p.66).
SELECTING A MEASUREMENT AREA - Click on one corner of the region using the left mouse button, and keep the button pressed. - Drag the mouse to the other corner of the region, and then release it. The size and the position of the square are shown in the Tool result panel. - Release the mouse button when the square’s size covers approximately one period of the grid. - Confirm the selection by double clicking the color map graph using the left mouse button.
A FIRST MEASUREMENT Storing the measurement When you are satisfied with your image and would like to keep it, you can take a snapshot of it by clicking the button. The behaviour of this button depends on whether a measurement is in progress or not. When a measurement is in progress, and is activated, a copy of the measurement is made to a measurement document after the measurement is finished. When the measurement is not in progress, a copy is made immediately.
FINISHING For an in depth introduction to the Nanosurf Report software, refer to the Introduction section of the Nanosurf Report online help. Finishing Once you are done measuring: - Click to stop measuring. - Open the positioning window. - Click . - Retract the cantilever to a safe distance from the sample by clicking until the tip-sample distance is at least as large as shown in figure View of the cantilever after manual approach (p.41).
IMPROVING MEASUREMENT QUALITY Improving measurement quality Removing interfering signals Interfering signals can be recognised because they have a fixed frequency, usually a multiple of the local mains frequency (50 or 60 Hz) throughout the image. Thus, they are manifested by straight lines that run throughout the image. Possible interference sources are: • Mechanical vibrations from machines or heavy transformers in the environment (e.g. pumps).
JUDGING MEASUREMENT QUALITY Electrical interference Electrical interference may be caused by interference in the electronics, or by electrostatic forces acting between the tip and the sample. Try the following in order to reduce the influence of electrical interference: - Connect the instrument to the mains power supply using sockets with line filters and surge protection.
IMPROVING MEASUREMENT QUALITY In the following cases the cantilever has to be replaced in order to re-establish high image quality: • images in the color map charts consist of uncorrelated lines only. • images appear blurred. - First follow the suggestions in section Image quality suddenly deteriorates (p.66). If these do not help, the cantilever should be changed. • If all peaks in the image have the same, usually triangular shape, the tip is no longer sharp and has to be replaced.
ADJUSTING THE MEASUREMENT PLANE Maladjusted slope: measurement with improperly set X*-slope 'Rotation' angle Measurement plane 'Y-Slope' angle Y* X* Image area 'X-Slope' angle Y X Scanner XY-plane Z, Z* Slope: Sample’s and measurement orientation before slope adjustment Average, Plane fit or higher order filters can not be used. • The Z-Controller functions less accurately, because it has to compensate for the sample slope.
IMPROVING MEASUREMENT QUALITY Ideally, the XY-plane of the scanner has already been correctly aligned with the sample plane using the three Levelling screws on the Scan head. However, this alignment can not be performed once the automatic approach has been done, because this will damage the tip. During measurement, the measurement plane should therefore be adjusted electronically using the parameters ‘X-Slope’ and ‘Y-Slope’.
ADJUSTING THE MEASUREMENT PLANE - Set Rotation to 90° to scan along the y-direction of the scanner. - If the scan line is not horizontal, alter the value for ‘Y-slope’ until the yaxis of the scan lies parallel to the y-axis of the sample. - Reset ‘Rotation’ to 0°. The Line graph shows the X-slope again.
MEASUREMENT MODES Measurement modes This chapter instructs you on how to use the Dynamic Force, Static Force, Phase contrast, the Force Modulation, and Spreading Resistance modes. If you are unfamiliar with the Atomic Force Microscopy Technique, it is recommended to first read the chapter AFM Theory (p.70). The amount of available modes depends on the Scan head and the available modules built into the easyScan 2 Controller.
DYNAMIC FORCE Both the Force Modulation mode and the Spreading Resistance mode are an extension of the Static Force mode. The procedure for a first Static Force mode measurement is basically the procedure described for the Dynamic Force mode in chapter ‘A first measurement’. The main differences are: - Use a suitable cantilever type (usually CONTR), and select this type in the Operating Mode panel. - Select the Static Force mode in the Operating Mode panel.
MEASUREMENT MODES vibration and a reference signal is measured. This phase shift changes when the resonance characteristic of the cantilever changes due to changes in the tip-sample interaction. Thus, the Phase contrast mode can be used to produce material contrast when there is a significant difference in the tip sample interaction of these materials.
PHASE CONTRAST Phase measurement In Phase contrast mode, the phase of the measured cantilever vibration is compared to the phase of a reference sine wave. The phase comparison is performed by multiplying the measured vibration signal with the reference.
MEASUREMENT MODES Force Modulation The Force Modulation mode is an extension of the Static force mode. The static force acting on the cantilever is still used to produce a topography image of the sample. Simultaneously, the cantilever is excited and the resulting vibration amplitude measured. The vibration amplitude depends on the drive amplitude, the stiffness of the cantilever and, most importantly, the stiffness of the tip-sample contact.
SPREADING RESISTANCE - If necessary, increase the size of the window to make space for the new chart. - Select the ‘Color map’ chart type by - Select the ‘Amplitude’ signal by . . Spreading Resistance The Spreading Resistance mode is an extension of the static force mode. The static force acting on the cantilever is used to produce a topography image of the sample.
MEASUREMENT MODES ple. • EFM cantilevers cannot be used, due to their insufficient width. - Install the cantilever as described in section Installing the cantilever (p.28). - Select the Spreading resistance mode in the Operating mode panel. - Open the Z-Controller panel. - Verify the force Set point. - Set the Tip voltage in the section Tip Properties. To display the measurement results: - Create a new chart in the Imaging window by clicking bar.
SIGNAL MODULE: S The Signal Modules The Signal Modules consist of both electronics modules that are built into the Controller, and a break-out Connector that is externally attached to the Controller. The Signal Modules can be used for monitoring the signals from (Signal Module: S) and adding functionality to (Signal Module: A) the easyScan 2 system. The Signal Module: A includes all the monitoring functions of the Signal Module: S.
THE SIGNAL MODULES Signal name Amplitude Phase Function The measured cantilever vibration amplitude. The measured cantilever vibration phase. The phase is affected by the Reference Phase Mode Property setting of the Phase Contrast Mode. Monitor Signals The calibration of the monitor signals can be found by looking up the signal calibration in the Scan Head Calibration Dialog, reached via the menu ‘Options>Config Scan Head...’.
SIGNAL MODULE: A their signal names. The signal names and their function are listed in the tables Monitor Signals and Signal Module: A Signals. Signal name Sync Function An output that can be used to synchronise external equipment with the Controller. This feature will be described in more detail in a future manual version (refer to the Nanosurf Web-site). User 1 Output An analog output that can be used to drive external instruments using the Controller.
THE SIGNAL MODULES Signal name User 1 Input User 2 Input Aux 1 Aux 2 Function An analog input that can be used to record the signal from external instruments in Imaging and Spectroscopy measurements. An analog input that can be used to record the signal from external instruments in Imaging and Spectroscopy measurements. A connector that can be used for accessing signals that are not otherwise available. Contact your local distributor if you need to use this connector.
SIGNAL MODULE: A Maintenance To ensure fault free operation of the microscope the following instructions for maintenance have to be followed. Scan head It is very important to keep the sample holder and the open part of the scanner clean. If exposed to moisture (high humidity), corrosion will occur. - Clean the alignment chip by blowing away dust using dry, oil free air or a soft brush. Scan electronics Clean the case and the controls with a soft cloth lightly moistened with a mild detergent solution.
PROBLEMS AND SOLUTIONS Problems and Solutions The problems described here can occur during normal operation of the microscope. If the suggested course of action does not solve the problem, or the problem is not described here, refer to the section Nanosurf support (p.68). Probe Status light blinks red This light will blink red when an insufficient amount of light reaches the cantilever deflection detector. This can be either be due to the DropStop still being closed or to a misaligned cantilever chip.
SIGNAL MODULE: A - Change the cantilever if no improvement can be seen after these procedures. Set point drift When part of the scan line in the Line graph is drawn red, the tip has moved to its maximum or minimum Z-position. This should also be visible in the range display on the right hand side of the graph.
PROBLEMS AND SOLUTIONS The USB cable is not properly connected. In this case the USB power light on the Controller rear panel (figure The easyScan 2 Controller (p.16)) does not light up. - Check that the USB cable is properly connected. Nanosurf support Self help The fastest way to solve a problem is often to solve it yourself. If the previously suggested actions did not help, or the problem is not described here, refer to the Nanosurf support pages: - Open www.nanosurf.com. - Click on support.
NANOSURF SUPPORT only happens when measuring in Dynamic Force Mode.’ • If an error message was displayed: The exact text of the message, or at least its start. • The serial number of your scan head and/or Controller. • A description of the computer hardware and software on which the control software is running: computer brand, type (lap-/desktop), operating system, software version etc. • Original Nanosurf image data (.
AFM THEORY AFM Theory Scanning Probe Microscopy The easyScan 2 AFM is an atomic force microscope, which is part of the family of scanning probe microscopes. When the first scanning probe microscope, the scanning tunneling microscope (STM), it became possible to look into the fascinating world of atoms. The STM was developed by Gerd Binnig and Heinrich Rohrer in the early 80’s at the IBM research laboratory in Rüschlikon, Switzerland.
THE NANOSURF EASYSCAN 2 AFM damping of the cantilever vibration caused by the forces between the tip and the cantilever can be measured and used for controlling the tip-sample distance. To achieve atomic resolution, ultra-clean and flat surfaces prepared in highly sophisticated vacuum systems are needed. Nevertheless, measurements in air can give useful results for many technically relevant surfaces. In this manual, the use of the dynamic modes in air on such technically relevant surfaces is described.
AFM THEORY Cantilever: 228 µm long micro-fabricated silicon cantilever with integrated tip In dynamic operating modes, the cantilever is excited using a piezo element. This piezo is oscillated with a fixed amplitude at an operating frequency close to the free resonance frequency of the cantilever. The repulsive force acting on the tip will increase the resonance frequency of the cantilever. This will cause the vibration amplitude of the cantilever to decrease.
THE NANOSURF EASYSCAN 2 AFM y x Scanner coordinate system 73
