Regardless of the type of SPM design, the device is sensitive to various influences and requires the use of special protection or compensation means. Their use allows to increase the resolution and accuracy of the data obtained.
You can see different types of SPM at the link - https://ilpa-tech.ru/produktsiya/zondovye-skaniruyushchie-rabochie-stantsii.
Vibration protection
SPM is an oscillatory system with a large spectrum of resonant frequencies. Under the influence of vibrations, resonance phenomena can occur, leading to excessive vibrations of the measuring heads, blurring of the image, and the appearance of parasitic noise.
Various vibration isolators are most often used to protect the device. They are divided into two types:
- Passive. They imply the placement of the device on a vibration-isolating platform. Due to this, only vibrations with a frequency corresponding to the resonance parameters of the vibration isolating structure will be transmitted to the SPM body. In this way, it is possible to effectively prevent the impact on the device of vibrations that can cause resonant phenomena in the scanning heads.
- Active. These are systems of active suppression of mechanical vibrations. The simplest varieties are built on the basis of a vibration sensor that transmits information to the SOS. It amplifies the signal, inverts and transmits to piezoelectric supports. Oscillations of the supports in antiphase with the vibrations registered by the sensor allow them to be completely extinguished.
Also, the mechanical stability of the scanning head can be affected by sound waves that directly affect the structural elements of the device. They provoke unpredictable vibrations of the probe near the surface under study.
To reduce acoustic interference, various caps are used to reduce the negative impact of this factor. It is also possible to completely eliminate the effect of sound, but this will require placing the instrument head in a vacuum, which is not always possible.
Compensation for temperature differences
Temperature fluctuations significantly complicate the stabilization of the probe at a given distance from the surface under study. This is due both to the influence of the ambient temperature and to the heating of various elements of the SPM during the study.
Uneven heating leads to the expansion of materials, although the deformations are microscopic, they noticeably affect the operation of the SPM. To reduce their impact, temperature control of the device is used, and compensatory elements are also introduced into their design. The latter consist of a set of materials with different degrees of thermal expansion, which makes it possible to practically level the effect of this factor on the stability of the probe.
Official supplier probe scanning stations in Moscow is the company IlPa Tech.
