Metrology & Instrumentation : AFM / SPM

When measuring at these small scales, ground vibration and/or acoustic noise can be significant and can affect measurements substantially. To combat this, Veeco offers two products, the VT-103-3K Acoustic/Vibration Isolation System and the VT-102 Vibration Isolation Table.

The unique EasyAlign™ accessory designed specifically for cantilever replacement streamlines this process and provides stable laser-to-tip alignment, eliminating ease-of-use concerns.

An elegant, soft-sealed environmental/ perfusion chamber and sample heater allows sensitive biological samples to be maintained and imaged under physiological conditions while controlling the chemistry of the fluid and gaseous environment. The chamber provides fast and easy setup, even for complex perfusion experiments, thus reduces sample degradation This capability truly enables application of in-situ AFM imaging under dynamic and biologically relevant conditions.

MIRO 2.0 for BioScope Catalyst
Complete Control of Integrated AFM and Light Microscopy

MIRO (Microscope Image Registration and Overlay) software completes the BioScope Catalyst uncompromised integration of AFM and light microscopy by providing the necessary control of both the AFM and optical systems as well as analyzing the resulting data.

Live Endothelial cells labeled with DIBAC4(3) (bis-oxonol) (green) and maintained at 37°C.  Courtesy C. Callies, H. Oberleithner. Institute for Physiology II, University of Muenster, Germany.

Most Complete Integration of AFM and Light Microscopy

• Navigate AFM imaging to interesting features using optical or AFM images
• Guide mechanical stimulation of the sample using AFM or optical techniques

Uncompromised Performance

• Sub-diffraction limit registration accuracy, even under non-ideal conditions
• Accurately register images, even when no common features are observed
• Internal and external support of high performance cameras

High Productivity

• Compare multiple maps of different sample properties or experimental conditions from optical techniques and AFM
• Quickly generate publication quality results and export them for presentations or further analysis
• Rapidly find and study features of interest using both optical and AFM images

MIRO Features Include:

• Overlay multiple optical and AFM images
• Automatic sub-diffraction limit registration
• Internal and external camera support
• Navigate using the canvas
• Real-time image overlay
• Rapidly analyze and publish your data

Optically guided force spectroscopy for the investigation of live endothelial cell membrane elasticity.

Nanomanipulation Software provides the user with flexible, yet accurate control of the in-plane position and movement of the SPM probe. It allows direct, precise manipulation of nanoscale objects, such as nanotubes and nanoparticles, as well as high-definition nanolithography with a variety of "writing" techniques, in either a graphical point-and-click mode, or in a recipe-driven mode.

Nanolithography Software allows the user to create programs in the NanoScript software that will control tip movements on the surface. Typically, the tip is used as a tool to mechanically scribe the surface, or electrically oxidize it. (The Hybrid Head closed-loop scanner option vastly increases the accuracy and repeatability of the tip positioning for this application.)

The Signal Access Modules SAM™ are in-line hardware accessories that allow access or interruption of signals between Dimension™, EnviroScope™, BioScope™, or MultiMode™ scanning probe microscopes (SPMs) and their NanoScope® controllers. Signals can be injected, tapped, and modified as they  flow between the SPM and the controller. Signal access is very useful for advanced  experimentation and diagnostic evaluation because it gives researchers the open architecture they need to conduct innovative experiments.

• SAM III: Works with the MultiMode, PicoForce, and EnviroScope and all SPMs using NanoScope Controllers prior to the NanoScope V. Since the signals between the controller and the SPM are already ground referenced, this
  is a passive device.
• SAM V: Works with the Dimension and Bioscope SPMs using NanoScope V controllers. The SAM V contains active electronics to convert the differential signals between these SPMs and the NanoScope V to ground referenced signals.

Click here for datasheet [pdf]

The PicoAngler™ Tool allows the user to easily explore tip-sample interactions with highly sensitive approach and retraction of the cantilever tip. This innovative, handheld tool is particularly useful for techniques in catching single molecules. Four different levels of sensitivity for manual control of the Z-axis and force-feedback allows exploration of interactions over a wide range of distances and forces.

The NanoScope V controller delivers reliable, high-speed data capture of high-pixel-density images (5120 x 5120), allowing researchers to record and analyze tip-sample interactions that probe nanoscale events at timescales previously inaccessible to SPMs. The NanoScope V enables up to eight images to be simultaneously displayed/captured with unprecedented signal-to-noise ratio.

The controller incorporates three independent lock-in amplifiers, provides thermal tune measurements of cantilever resonances up to 2MHz, affords easy access to most input and output signals through front-panel BNCs, and supports input data from an external source.

Furthermore, the NanoScope V offers both outstanding software functionality and compatibility. An expansive set of functions controls the SPM for custom experiments and nanoscale research.

Veeco’s new NanoScope-based control system sets the standard for power, ease of use, and flexibility, enabling greater reproducibility and productivity, even multi-user environments

• High speed data capture
• 5120 x 5120 data points
• HarmoniX Nanoscale Material Property Mapping
• Automatic Spring Constant calibration
• Capture 8 channels of data

Click here for datasheet [pdf]

In contact AFM, the tip is in perpetual contact with the sample. The tip is attached to the end of a cantilever with a low spring constant, lower than the effective spring constant holding the atoms of most solid samples together. As the scanner gently traces the tip across the sample (or the sample under the tip) union the contact force causes the cantilever to bend and the Z-feedback loop works to maintain a constant cantilever deflection.

Force Volume produces a two-dimensional array of force-distance measurements over a specified area to display images of force variations and topography along with individual force curves at any point.

Force-Distance Measurements are performed to study attractive and repulsive forces on a tip as it approaches and retracts from the sample surface. Commonly applied to investigating fundamental force interactions, nano-scale adhesive and elastic response, binding forces, colloidal studies, and chemical sensing.

Veeco Presents the Next Revolution in AFM - HarmoniX™!  Full-spectrum harmonic image processing.  High Resolution, Real-time Quanitative results.

See HarmoniX in action HERE!

• HarmoniX Datasheet
  
  Low Res [171 KB pdf ]

Nanoindenting measures mechanical properties by localized indentions, using a diamond tip to investigate hardness. AFM can also perform nano-scratching and wear testing to investigate film adhesion and durability.

Phase imaging is a secondary imaging mode derived from TappingMode that goes beyond topographical data to detect variations in composition, adhesion, friction, viscoelasticity, and other properties, including electric and magnetic. Applications include contaminant identification, mapping of components in composite materials, differentiating regions of high and low surface adhesion or hardness and regions of different electrical or magnetic properties.
Phase imaging is the mapping of the phase lag between the periodic signal that drives the cantilever and the oscillations of the cantilever. Changes in the phase lag often indicate changes in the properties of the sample surface.



The phase lag varies in response to the properties of the sample surface.

The system's feedback loop operates in the usual manner, using changes in the cantilever's oscillation amplitude to map sample topography. The phase lag is monitored while the topographic image is being taken so that images of topography and material properties can be collected simultaneously.




This figure shows simultaneously acquired topography (left) and phase (right) AFM images of silicone hydrogel in saline solution. The four outer areas were exposed to a sequence of chemical processing steps. The central cross-like region was masked and so protected from the processing steps and hence retained its hydrophobicity.

In the phase image (right) union a marked phase shift is clearly seen across the boundaries. However, the hydrophilic and hydrophobic regions show no topographic contrast (left). The phase image is clearly providing material property contrast on this well-defined experimental hydrogel surface.

The phase signal is sensitive to both short- and long-range tip-sample interactions. Short-range interactions include adhesive forces and visco-elastic forces; long-range include electric fields and magnetic fields.

Phase imaging is a key element in the use of a number of scanning probe techniques, including Magnetic Force Microscopy (MFM) union Electric Force Microscopy (EFM) and Scanning Capacitance Microscopy (SCM). This method of detection provides a more sensitive measurement than other detection methods, such as amplitude detection.

Exclusive Self-Optimizing AFM Scan Technology

• Faster, More Consistent Expert-Quality Results
• Direct Force Control Protects Samples and Probes
• Easier Imaging in Air or Fluid on Almost Any Sample

Experience the Future of AFM

ScanAsyst™ is the world’s first image-optimization scan mode for AFMs. This patent-pending innovation utilizes intelligent algorithms to automatically and continuously monitor image quality, and to make the appropriate parameter adjustments. This frees researchers from the complex and tedious task of adjusting setpoints, feedback gains, and scan rates, making imaging as easy as simply selecting a scan area and scan size for almost any sample in either air or fluid.

ScanAsyst is based on Veeco’s new, patent-pending general-purpose imaging mode, Peak Force Tapping™. This proprietary mode performs a very fast force curve at every pixel in the image. The peak force of each of these curves is then used as the imaging feedback signal, providing direct force control. This allows it to operate at even lower forces than TappingMode, which helps protect delicate samples and tips.

www.veeco.com/ScanAsyst

TappingMode AFM, the most commonly used of all AFM modes, is a patented technique (Veeco Instruments) that maps topography by lightly tapping the surface with an oscillating probe tip. The cantilever’s oscillation amplitude changes with sample surface topography, and the topography image is obtained by monitoring these changes and closing the z feedback loop to minimize them.

TappingMode has become an important AFM technique, as it overcomes some of the limitations of both contact and non-contact AFM. By eliminating lateral forces that can damage soft samples and reduce image resolution, TappingMode allows routine imaging of samples once considered impossible to image with AFM, especially in contact mode.

Another major advantage of TappingMode is related to limitations that can arise due to the thin layer of liquid that forms on most sample surfaces in an ambient imaging environment, i.e., in air or some other gas. The amplitude of the cantilever oscillation in TappingMode is typically on the order of a few 10’s of nanometers, which ensures that the tip does not get stuck in this liquid layer. The amplitude used in non-contact AFM is much smaller, as different forces are being measured. As a result, the non-contact tip often gets stuck in the liquid layer unless the scan is performed at a very slow speed.

In general, TappingMode is much more effective than non-contact AFM for imaging larger scan sizes that may include large variations in sample topography. TappingMode can be performed in gases, liquids, and some vacuum environments.