Calculation of the Effective Dielectric Constant and Capacitance of Slit and Plane-Parallel Capacitors with High Temperature Stability Characteristics Based on a Multilayer Ferroelectric Structure

Introduction. The creation of a modern electronic component base with improved characteristics is possible with the use of new materials and technologies for their manufacture. Therefore, it is important to analyze the electrical parameters of electronic components when using materials in their design that expand their functionality. Stabilization of the electrical properties of capacitors with variable capacitance when the control voltage changes due to temperature influences is an urgent task. Its solution can be performed using a set of nonlinear dielectrics, the properties of which mutually compensate for the instability of the capacitance over a wide temperature range.

Aim. Creation of computational models of planar slit structures containing multilayer films with thickness-variable stoichiometric compositions of ferroelectric materials. Based on such structures, it becomes possible to design capacitors whose capacitance varies from the control voltage and which can be used as concentrated circuit elements operating in the low–frequency - microwave wavelength ranges and having high temperature stability.

Materials and methods. Computational mathematical models for the analysis of layered structures are performed using the method of conformal maps and the use of boundary conditions for tangential and normal components of the electric field.

Results. The capacitance of slit and plane-parallel capacitors on multilayer structures is analyzed. The results of calculating the capacitance of capacitors from the number of ferroelectric layers and their thicknesses with various stoichiometric compositions providing the required stability in a given temperature range are obtained. Increasing the number of layers in the structure from three to five expands the temperature range of stabilization of the effective dielectric constant of the tank from ~50 °C to ~120…160 °C.

Conclusion. The created mathematical models made it possible to numerically evaluate the temperature and field stability of multilayer film structures based on barium strontium compositions for their use as a basis for constructing a component base with electrical capacity adjustment.

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