Electrical Characterization on the Nanoscale
The Nano-Observer AFM offers several techniques to obtain electrical properties:
- Electric Force Microscopy (EFM)
- Kelvin Probe Force Microscopy (KFM)
- ResiScope Mode (Conducting or SSRS AFM)
These modes require a conducting tip and are used to measure the following properties:
Electrostatic Force: EFM uses an oscillating tip to scan the surface twice - once to measure topography and the second time offsets to measure changes in the field gradients.
Surface Potential: KFM uses an oscillating tip to measure the work function of surfaces. This can be operating in dual-pass or in High Definition KFM mode that uses 2 lock-ins to acquire both topography and surface potential in a single pass.
Electrical Resistance or Conductivity: Conducting AFM is used to measure the conductivity (or inversely, resistivity) of a surface by scanning a tip in contact mode and measuring the current between the sample and biased tip. The Nano-Observer AFM has a unique ResiScope that provides specialized electronics to measure resistivity over 10 orders of magnitude, compared to the typical 3-4 orders standard in other AFMs. Standard conducting AFM is available, as well as a Soft ResiScope that uses an intermittent contact technique at constant force for soft or fragile samples.