DEVELOPMENT OF A UNIVERSAL METHODOLOGY FOR MEASURING THE PARAMETERS OF MICROSCOPIC STRUCTURAL DEFECTS IN SOLID STATE DIELECTRIC

Abstract

A universal methodology is proposed for measuring (based on an improved experimental setup) and calculating the parameters of microscopic structural defects involved in the formation of volume-charge polarization in dielectrics with a complex crystal structure (hydrogen bonded crystals (HBC); various types of ceramics; perovskites; alkali-halide crystals, etc.). The method of thermally stimulated depolarization currents, in combination with the measurement of the dielectric loss tangent, makes it possible to perform dielectric spectroscopy of hydrogen bonded crystals (HBC) and to analyze the properties and parameters of structural defects. A circuit for measuring the thermally stimulated depolarization current (TSTD), automated with the help of a computer sound card, by the method of modulation - demodulation (MDM - method) of the signal, has been developed. Practical approbation of this scheme was carried out by measuring the temperature spectrum of the density of TSTD, compared by the method of minimizing the comparison function (MCF), with theoretical dependences calculated by the methods of the kinetic theory of proton relaxation in HBC, using the example of a natural phlogopite crystal. By statistical processing of experimental errors, a high degree of accuracy of the computerized measurement scheme is substantiated.