Dislocation identification method of silicon carbide crystal

Abstract

The invention provides a dislocation identification method of a silicon carbide crystal. The method comprises the following steps: (1) corroding the silicon carbide crystal in an alkaline corrosive agent; and (2) after the corrosion is completed, observing the morphology of a dislocation corrosion pit so as to identify blade dislocation, screw dislocation and base plane dislocation in the siliconcarbide crystal, wherein the silicon carbide crystal comprises high-purity silicon carbide and nitrogen-doped silicon carbide, the corrosion time of the high-purity silicon carbide is 5-7 minutes, andthe corrosion time of the nitrogen-doped silicon carbide is 7-9 minutes. According to the method, the corrosion time of alkaline corrosion is optimized, and the corrosion time of high-purity siliconcarbide and nitrogen-doped silicon carbide is controlled to be less than 10 minutes so that three dislocations including edge dislocations, screw dislocations and base plane dislocations in the high-purity silicon carbide or the nitrogen-doped silicon carbide can be accurately distinguished; the corrosion time is short; and three dislocations in the crystal can be accurately identified.

Description

technical field [0001] The invention relates to a method for dislocation identification of silicon carbide crystals, belonging to the technical field of test and characterization of crystal materials. Background technique [0002] As a new type of power component material, silicon carbide has attracted widespread attention because of its high resistivity, high strength and good thermal conductivity. However, due to the high requirements for its growth conditions, the defects introduced during the growth process limit the improvement of its performance and its further application and development. Therefore, the characterization and statistics of defects become the first prerequisite for improving the defects. Dislocation, as a kind of line defect, can be divided into edge dislocation (TED), screw dislocation (TSD) and basal plane dislocation (BPD) according to the difference of its formation mechanism and the difference of semi-atom plane. Different dislocations and their d...

AI Technical Summary

Problems solved by technology

In this method, KOH, NaOH or a mixture of the two is used as the etchant, and the etching time is 10 to 35 minutes. This method can accurately determine the types of mixed dislocations, screw dislocations and edge dislocations in silicon carbide crystals. The identification of edge dislocation, screw dislocation and basal plane dislocation cannot be realized at the same time, and the corrosion time is long

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