Atomic Force Microscopy (AFM)

AFM collects surface topography information using a reflected laser beam on top of a cantilever, which has an atomically sharp tip that scans the sample surface. This technology is based on the Scanning Probe Microscopy (SPM) principle, which uses piezo-electric materials for ultra-fine control of the tip unit movement. The cantilever tip scans over the sample surface in three different modes: tapping mode, contact mode and non-contact mode. Typically, contact mode is used for quick imaging of rough samples, tapping mode for fluid layer analysis, and non-contact mode under ultra-high vacuum (UHV) condition. These different modes create feedback from the sample surface, and from there the images are formed.

The current limitations of AFM are due to the size and curvature of the probe tip. For analysis at the atomic level, the size of the probe tip would need to be smaller than the width of a single atom. Another limitation is the resolution of AFM images comes from the curvature of the scanning tip; as the radius of the tip increases the resolution of the image decreases.

There are many variations of AFM depending on the type of interaction forces (between sample surface and the cantilever tip) it uses - such as Van der Waals force, electrical resistance or capacitance, magnetics, electrochemical, fluidic forces and so on.

Here are some examples of when to use AFM analysis:

Thin Films and Coatings
Tribology (surface and friction interaction)
Surface Chemistry
Polymer Chemistry and Physics
Energy storage (battery) and Energy Generation (photovoltaic) materials
Piezoelectric and Ferroelectric Materials
Characterization of Graphene Composite Materials

To read more on AFM, you can read our Key Tech brochure.

Services

Surface morphology analysis of thin film or bulk materials
Scanning Capacitance Microscopy (SCM) to get the active dopant profiles from semiconductor or LED devices/materials
Scanning Spread Resistance Microscopy (SSRM) to measure the resistance profiles

Pricing

Pricing for AFM and other Materials Analysis services are provided on our Pricing Table

FAQ

Q: What is AFM used for?: A: This tool is typically used to visualize the surface topography and to quantify the surface roughness.
Q: How do you analyze AFM data?: A: AFM images consists of relative height information of pixels, which is used for various type of quantitative analysis.
Q: How does AFM measure thickness or the height of features?: A: From the step height or the line profile measurements whose resolution can be sub-nano meter scale
Q: What is the typical area size of AFM measurements?: A: Typical ambient AFM can analyze from 0.1um x 0.1um to 200um x 200um area range.
Q: Is AFM destructive or non-destructive?: A: It is a non-destructive analysis method. However, some variation technologies of AFM, such as scanning spread resistant microscopy (SSRM) alters the surface structure as it pushes the tip with high pressure toward the surface.

Equipment

Park System NX 20 Atomic Force Microscope

Highly accurate AFM from Park Systems designed for failure analysis and quality control research. Park’s innovative anti-vibration technology keeps actual noise levels below 0.5 Å or 0.3 Å RMS

XY Scanner: 100 μm x 100 μm
XY Travel Distance: 300 mm x 300 mm
Z Travel Distance: 25 mm
Focus Stage Travel Distance: 8 mm
Vacuum groove holder: 100, 150, 200, 300 mm wafer compatible, small sample magnetic fixing holder, up to 20 mm thick

Read more about the Park System NX 20 AFM here.