3 results about "Threading dislocations" patented technology

This application provides an apparatus and method for reducing the density of through-type dislocation defects in silicon carbide crystals. The apparatus includes an insulation component formed by an upper insulation layer, a first outer insulation layer, and a lower insulation layer. The insulation component is provided with gas exchange channels. By placing a crucible containing a silicon carbide seed crystal and silicon carbide raw material into the insulation component and placing them together into a single crystal growth furnace, silicon carbide crystal is grown according to the parameters set for each growth stage to obtain an N-type silicon carbide crystal. When in the isothermal section, N2 is introduced into the single crystal growth furnace in a cycle of n periods according to a first flow rate state and a second flow rate state. Nitrogen is intentionally doped into the silicon carbide crystal during the growth process through the gas exchange channels to increase the conversion probability and ejection probability of through-type dislocations to basal plane dislocations and stacking faults in the N-type silicon carbide crystal. This solves the problem of high dislocation density in SiC single crystals grown by the current PVT method.

A light emitting element includes an n-type semiconductor, a p-type semiconductor, and an active layer between the n-type semiconductor and the p-type semiconductor, threading dislocations are formed in the n-type semiconductor, and openings are formed on a surface of the n-type semiconductor based on the threading dislocations.

The application provides a method for identifying penetrating dislocations in silicon carbide, and the method comprises the following steps: performing preliminary etching on a silicon carbide sample to be identified; selecting a suitable diffraction vector; calculating relevant parameters corresponding to X-ray topography detection under the selected diffraction vector by using Bragg diffraction principle, the relevant parameters containing an incident angle; observing TSD and TED etch pits of the preliminary etched silicon carbide sample; recording an included angle between a line connecting the highest point and the lowest point of the selected etch pit and a horizontal line; obtaining an average value of the included angle of the selected etch pit; multiplying the average value of the included angle by a fixed coefficient to obtain a coefficient included angle; comparing the coefficient included angle with the incident angle of the selected diffraction vector; if the coefficient included angle is greater than the incident angle, directly performing X-ray topography detection; otherwise, etching again; and identifying by using an image of the X-ray topography detection. The application can effectively realize positioning and counting of different types of dislocations in silicon carbide.