LETI: LETI Researchers Know How to Improve Microwave Devices

A device based on a multilayer ferroelectric/silicon carbide structure can improve the efficiency of ultrahigh-frequency systems.

Radar and communication systems are based on ultrahigh-frequency (UHF) electronics technology. Now, microwave devices based on semiconductor and ferrite materials used in these systems have several drawbacks. Among these disadvantages are large microwave losses, low speed, and high power consumption. Therefore, researchers explore alternative materials with new properties and technologies to improve the operating parameters of microwave electronics.

One way to solve the existing problem of imperfect components for microwave devices is ferroelectric materials, which are superior in many electrophysical characteristics to both semiconductors and ferrites.

“There is a whole class of ferroelectric materials with high dielectric permittivity that are promising for microwave applications. Controllable microwave devices can be created based on ferroelectric materials: variable capacitors, phase shifters, delay lines, controllable filters.”

Andrey Tumarkin, Professor of the Department of Physical Electronics and Technology at LETI
The results of the LETI scientists’ research offer an alternative to semiconductor and ferrite materials for ultrahigh-frequency devices. The project implemented by the research team of the Department of Physical Electronics and Technology consisting of Associate Professors Andrey Altynnikov, Roman Platonov, and Assistant Professor Evgeny Sapego under the guidance of Professor Andrey Tumarkin won a grant of the LETI Youth Innovation Projects Contest.

The scientists developed a ferroelectric phase shifter, an ultrahigh-frequency component capable of controlling the phase of the microwave signal by changing the dielectric permittivity of the ferroelectric material under the influence of the electric field. The device is a multilayer structure consisting of ferroelectric and conducting layers on a silicon carbide substrate and is designed to operate at high microwave power.

“The advantage of our developed phase shifter is the use of a silicon carbide substrate, a material with high thermal conductivity, which makes it possible to increase the operating power of the device and avoid overheating it.”

Evgeny Sapego, Assistant Professor of the Department of Physical Electronics and Technology at LETI
At the moment, the researchers test electrophysical and power characteristics of the experimental prototype of the phase shifter together with colleagues from Rohde & Schwarz.