ETU "LETI" researchers developed a unique method for electromagnetic compatibility of electronic devices
Protecting electronic devices from electromagnetic interference, that is, controlling their electromagnetic compatibility (EMC), became important simultaneously with the advent of electronics. The problem of EMC has become even more acute in the last decade due to the constantly decreasing mass and size of electronic devices and their increasing frequency. The number of domestic and industrial sources of electromagnetic interference, including cellular networks with several simultaneously operating standards (1G, 2G, 3G, 4G, and now 5G), wireless access points to the Internet (also different frequency ranges - 2.4 GHz, 5.0 GHz, etc.) has sharply increased. The mass use of various electronic devices leads to unintentional mutual interferences, which hinder and often exclude the possibility of proper joint work.
Scientists around the world are solving the problem of electromagnetic compatibility of electronic devices. They try to solve the issue using materials science (creation of radiation-absorbent and shielding materials), circuitry (development of interference-resistant electronic devices), and software (application of software tools to increase resistance to interference). All these developments involve the use of new, more complex, and expensive technologies.
Researchers of St. Petersburg Electrotechnical University "LETI" developed a unique, reliable, and affordable way to control electromagnetic compatibility. They proposed using the well-known radiation-absorbent fillers as part of a new composite based on conductive polymer polyaniline. The results of the study were published in the journal Electronics.
Employees of the Engineering Center for Microtechnology and Diagnostics and the Department of Micro- and Nanoelectronics of ETU "LETI" carry out research under the guidance of Professor Viktor Luchinin.
"Research into the development of new materials for EMC, which includes work at the Engineering Center for Microtechnology and Diagnostics, involves new, usually more complex, and costly technologies for obtaining such materials. This approach makes it possible to achieve very high shielding efficiency and electromagnetic radiation absorption in laboratory conditions. However, when trying to introduce such new technologies into the industry, they most often turn out to be either too expensive or unsuitable for scaling, or not reproducible at all due to lack of qualified specialists and some other reasons," Professor Luchinin says.
"Our main idea during the development was to offer an accessible, reliable, and ultimately implemented in the industrial production method for EMC of electronic devices using known radiation absorbent fillers in the new composite."
Professor Viktor Luchinin, Head of the Department of Micro- and Nanoelectronics of ETU "LETI"
The idea of scientists is to use a dielectric polymeric composite film made of gelatin, which contains distributed absorbing electromagnetic radiation particles of conductive polymer (polyaniline).
The chosen approach allowed to achieve at a small thickness of material a high coefficient of absorption of electromagnetic radiation in the range of frequencies of household sources of electromagnetic interference. At the same time, the proposed approach made it possible to directly apply the material on the already finished electronic circuit boards, as the temperature of application is 60° C, and the material itself does not cause a short circuit between the elements on the circuit board, because it is a dielectric.
"Thanks to the simple low-temperature method of application of developed composites, absence of through conductivity, and low dielectric permittivity, they can be applied directly to electronic printed circuit boards. They can also protect the components placed on them from RF interference from industrial and domestic sources, including signals from cellular network stations, digital television, wireless Internet access points."
Kamil Gareev, Associate Professor of the Department of Micro- and Nanoelectronics of ETU "LETI"
Scientists plan to conduct tests to apply layers of the composite to electronic circuit boards and assess their resistance to electromagnetic interference of different frequencies, effects of climatic factors (high humidity and temperature), vibration, etc. Next, Petersburg researchers plan to patent the technology and search for possibilities to introduce it at industries of ETU "LETI" partners.