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In this paper, we present a simple non-destructive method for testing SiC plate single crystals of any size and shape. The method is based on measuring the impedance changes of an inductive ferrite-cored coil due to placing the sample into the core gap. The method is valid for any SiC polytypes, though we used 6H one. Using this method we have obtained and discussed a conductivity as a function of doping level (N d –N a ) for 6H–SiC Lely crystals. The conductivity measurements were carried out with alternating current of 747 kHz frequency. The sensitivity of the method is limited by minimal conductivity 1 Ω −1 cm −1 (that is corresponding to (N d –N a )∼2×10 16 cm −3 for 6H–SiC : N Lely crystals).

In this paper we present a simple non-destructive method for testing SiC plate single-crystals of any size and shape. Themethod is based on measuring the impedance changes of an inductive ferrite-cored coil due to placing the sample into thecore gap. The method is valid for any SiC polytypes, though we used 6H one. Using this method we have obtained anddiscussed a conductivity as a function of doping level (NdNa) for 6H-SiC Lely crystals. The conductivity measurements were carried out with alternating current of 747 kHz frequency. The sensitivity of the method is limited by minimal conductivity 1 (Ohnrcm)1 (that is corresponding to (NdNa) 2•1016cnf3 for 6H-SiC:N Lely crystals).Keywords: high frequency; non-destructive, special conductivity, silicon carbide. 1. INTRODUCTION The problem we consider is the non-destructive measurement of the conductivity of small irregular SiC crystals, which are commonly used in scientific laboratories. Note that the contact measurement of the conductivity of wide band gapsemiconductors is possible only with specially treated contacts. There is a good way to solve the problem

Summary form only given. A simple non-destructive method for characterising SiC samples (Lely-crystals, CREE-substrates, and epitaxial films) is presented. The observed ultraviolet differential reflection spectra of SiC samples were compared with a pure Lely-crystal (model sample) to estimate the structural quality of the sample. The method presented is based on a differential study of ultraviolet reflection spectra of SiC films in comparison with a perfect Lely-crystal.