AlGaN-based deep ultraviolet light emitting diode, and AlGaN epitaxial wafer and preparation method thereof

Abstract

The invention relates to an AlGaN-based deep ultraviolet light emitting diode, and an AlGaN epitaxial wafer and a preparation method thereof. The AlGaN-based deep ultraviolet light emitting diode andthe AlGaN epitaxial wafer each adopt a single-layer graphical BN buffer layer as a buffer layer, and the characteristic that Van der Waals' force is adopted between layers of a single-layer BN is utilized, so that the stress in the epitaxial layer can be effectively reduced; by utilizing the characteristic that the single-layer BN and the epitaxial layer belong to III-group nitrides, better epitaxial compatibility can be achieved; furthermore, the characteristic that the pattern density and the pattern size of the patterned BN buffer layer are controllable is utilized, thus the uniformity anddensity of the nucleation center position during nitride growth can be controlled, so that the crystallization quality of the AlGaN epitaxial wafer is improved, the dislocation density of the AlGaN epitaxial wafer is reduced, and the internal quantum efficiency of the AlGaN epitaxial wafer is improved.

Description

technical field [0001] The present invention relates to a deep ultraviolet light-emitting diode, in particular to an AlGaN-based deep ultraviolet light-emitting diode with high internal quantum efficiency, its AlGaN epitaxial wafer and a preparation method thereof, the AlGaN-based deep ultraviolet light-emitting diode and the AlGaN epitaxial wafer are both A single-layer patterned BN buffer layer is used as the buffer layer. Background technique [0002] According to different wavelength ranges, ultraviolet light can be divided into: long-wave ultraviolet UVA (320nm-400nm), medium-wave ultraviolet UVB (280nm-320nm), short-wave ultraviolet UVC (200nm-280nm) and vacuum ultraviolet Vacuum UV (10-200nm). Ultraviolet light with a wavelength of 200nm-350nm is called deep ultraviolet light. Deep ultraviolet light-emitting diodes have the advantages of energy saving, environmental protection, safety, long life, low consumption, and low heat. Therefore, deep ultraviolet light-emitti...

AI Technical Summary

Problems solved by technology

[0004] At present, the main problem restricting the development of AlGaN-based deep-ultraviolet light-emitting diodes is the lack of substrate materials that match the AlGaN lattice. There are large lattice mismatches and differences in thermal expansion coefficients, resulting in more threading dislocations in the nitride films and devices grown on the substrate. These dislocations have an impact on the internal quantum efficiency of AlGaN-based deep ultraviolet light-emitting diodes. The internal quantum efficiency of extremely large and high dislocation density AlGaN multiple quantum wells is only 1%. If you want to obtain a deep ultraviolet light-emitting diode with an internal quantum efficiency greater than 60%, the dislocation density of the material needs to be lower than 5×10 8 cm -2

Images