Atomic Force
Microscopy
Chemical & Physical
Analysis
PSIA XE-100 atomic force microscope
Atomic force Microscopy (AFM) is a powerful technique that can image the topography of a surface with nanometer resolution, as well as probe its local mechanical and electrical properties. AFM is routinely used to evaluate the surface structure of:
- Semiconductors
- Polymers
- Adhesive materials
- Biological samples
The XE-100 AFM at Southwest Research Institute (SwRI) operates in various contact and noncontact modes to measure different surface properties:
- Image soft biological samples without degrading the sample using the noncontact mode.
- Phase images from the noncontact mode can also indicate regions of different adhesion and stiffness.
- Reveal areas of different frictional force on an heterogeneous surface by monitoring the lateral force in contact mode.
- Use the electrostatic force mode to probe the local electrical properties of a surface by applying a voltage between the sample and a conductive AFM tip.
The AFM accepts sample sizes as large as 100 mm × 100 mm × 20 mm thick, with masses up to 500 g. The X-Y scanner can image areas as large as 50 μm × 50 μm, with a resolution of <0.15 nm. The Z scanner can measure surface features as high as 12 mm, with a resolution of <0.05 nm.
The topography (left) of a conductive semiconductor device shows a series of interlocking “fingers” separated by trenches. The electrostatic image (right) shows every other finger carries a voltage, while the others are grounded.
Related Terminology
atomic force microscopy • XE-100 AFM • surface analysis • scanning probe microscopy • SPM • nanometer resolution • materials characterization • biological analysis • analytical services • rheology and texture analysis • microscopy • nanometer resolution • spectroscopy • noncontact mode • electrostatic force mode • contact mode
