Scanning Probe Microscopy
Todays,
many users, which have been associated in different shapes to analyzing
the surface and thin layer, however, have probably sufficient
information, about the SEM and TEM electron microscopy, but their
information is limited and often incomplete data about relatively new
generation of microscopes, called scanning probe microscopes.
Usually,
the most of them also know SPM microscopes as a new microscope, which
offers only information about the surface topography. This is while, the
world of scanning probe microscopes is very broad, and includes
analysis of many properties of the surface, which sometimes electron
microscopes are not able to do it.
Unlike initial impressions, it
doesn't represents alone a special microscope but rather represents a
collection of microscopes with different capabilities, which are used
for determining the surface properties at the nanometer scales, and at
them the sample surface to be scanned instead of electrons with a
special probe. Today there is almost no advanced laboratory in the field
of thin film, surface and nanotechnology, in which there isn’t scanning
microscopes.
The scanning microscope SPM, there are in different
modes, depending on the type of performance. Modes of AFM, STM, LFM, MFM
and SNOM, are the most important modes of scanning probe microscopes,
which with their help can be extracted the information about the thin
film surface, which continues to be discussed.
Figure 1: overview of the needle tip scanning over the sample surface.
Generally, a scanning microscope is composed of four main parts:
1. The main base that according to Figure 2 includes: desk, glass plate and probe holder.
2- Scanner
3. The controller system.
4. The Software of SPM.
Figure 2: An example of SPM base and scanner manufactured by DME.
The main parts of the microscope are:
1. Desk X-Y
2. Glass plate
3. Scanner
4. The holder of the scanner
5. CCD Camera.
For
perform analysis, first sample is placed carefully on the base and the
sample surface is scanned by a special probe, which is mounted on the
scanner. Resulted signals from the scanning probe go to the controller,
as shown in Figure 3, and this information is transferred to the
computer after the initial processing in the controller, as shown in
Fig. The existing software on the computer starts to rebuild the image
and form the multiple images (two or three-dimensional), in different
modes, after reprocessing the received data from the controller.
Figure 3: Schematic view of SPM system,1. Computer 2. Controllers 3. Microscope.