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Glossary terms about Scan

The experiment carried out in scanning probe microscopy.

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28 pages mention Scan

AFM calibration methods
S. scanning force microscopy - Calibrative procedures for 'best practice'. 
AFM imaging of surfaces
Journal Link... Pandey, D., Reifenberger, R., et al. scanning probe microscopy study of exfoliated oxidized graphene sheets. 
AFM imaging: Interactions between the probe and sample
As the probe tip scans the surface at this close distance, a feedback system to the piezoelectric scanner raises and lowers the sample to keep a constant repulsive force between the tip and the sample surface. 
AFM papers
L., et al. Recent Advances in Atomic-Force Microscopy of DNA. scanning 15(5): 296-299, 1993. 
AFM probe modification
L., et al. High-yield assembly of individual single-walled carbon nanotube tips for scanning probe microscopes Journal of Physical Chemistry B 105 (4): 743-746, 2001. 
AFM: Background information
The Atomic Force Microscope (AFM) operates by scanning an AFM probe across a sample surface. 
Cantilever tuning - only for tapping and non-contact modes
This is almost always an automated process in the AFM software, and all the operator has to input is the frequency range to scan over and the target amplitude of the cantilever. 
Contact mode
Contact mode/ constant force AFM operates by scanning the tip across the sample surface while monitoring the change in cantilever deflection with a split photodiode detector. 
The area scanned is 40 x 40 microns. 
How is the Data Displayed?
Most scanning Probe experiments produce data as a function of the sample's x and y position. 
Image artefacts
Thermal expansion may result in the sample becoming 'loose' on the stage and moving as the sample is scanned. 
Image Scanning and feedback parameter optimisation - scan rate
scan rate  
Rohrer, from IBM research laboratories, invented a new type of microscope called a scanning tunnelling microscope (STM). 
Laser alignment on cantilever
If not performed properly then a number of artefacts can result including, for example, excessive force being applied to the surface when scanning and optical interference fringes from reflective surfaces can be detected. 
Near-field scanning optical microscope (NSOM/SNOM)
Review articles
S., et al. scanning force microscopy - Calibrative procedures for 'best practice'. 
Scanner artefacts
Piezoelectric elements in scanners are used to position the probe tip relative to the sample surface at the nanometer scale with great accuracy. 
Scanning probe microscopy in practice
Scanning Tunneling Microscopy (STM)
STM is the oldest of the scanning probe microscopes and involves bringing an atomically sharp tip within a couple of nanometres of the sample. 
Set point - Tapping mode
Then repeat until maximum image quality is achieved. 
Set-point - contact mode
In contact mode the set-point refers to the deflection set-point of the cantilever, and is the cantilever deflection (usually given in Volts or nanoAmps) at which the AFM will scan, and is determined by the operator. 
Specimen choice
The AFM piezoelectric scanners are usually limited to a maximum vertical movement of approximately five microns with a maximum x-y range of 100 x 100 microns. 
Tapping mode
Tapping Mode AFM operates by scanning a tip attached to the end of an oscillating cantilever across the sample surface. 
There are many varieties of scanning probe microscope (SPM) techniques ranging from the most common which are atomic force microscopy (AFM) and scanning tunnelling microscopy (STM), to more specialised instruments such as the near-field scanning optical microscope (NSOM/SNOM), tip-enhanced Raman microscope (TERS), and lateral force microscope (LFM) among others. 
Tip artefacts
Artefacts result from the tip either becoming contaminated by material on the sample surface or from wear due to scanning. 
Virtual Scanning probe microscopy
Please select which sample you would like to view under the scanning probe microscope. 
Virtual SPM - Calibration grid
Interactive simulation of a scanning probe microscope. 
Virtual SPM - Nanotubes
Interactive simulation of a scanning probe microscope.