Ultraviolet led epitaxial wafer and its preparation method and application

Abstract

The invention discloses an ultraviolet LED epitaxial sheet and its preparation method and application, wherein the ultraviolet LED epitaxial sheet includes an n-type semiconductor layer, an active layer, an electron blocking layer and a p-type semiconductor layer which are epitaxially grown in sequence; the electron blocking layer consists of a first The first sublayer and the second sublayer are alternately grown in a superlattice structure, the first sublayer is an aluminum boron nitride layer, and the second sublayer is an aluminum gallium nitride layer. The ultraviolet LED epitaxial wafer provided by the present invention uses alternately grown aluminum boron nitride layers and aluminum gallium nitride layers to form an electron blocking layer, so that the energy level position of the conduction band of the electron blocking layer is higher, and the effective barrier height of electrons is increased, effectively Block electrons from transitioning to the p-type semiconductor layer; at the same time, reduce the hole barrier height between the electron blocking layer and the active region, and significantly improve the injection efficiency of holes injected into the active layer; therefore, the radiative recombination rate of the active region can be increased, Thereby improving the luminous efficiency of the ultraviolet LED.

Description

technical field [0001] The invention relates to the technical field of diodes, in particular to an ultraviolet LED epitaxial wafer and a preparation method and application thereof. Background technique [0002] An ultraviolet light emitting diode (LED) generally includes an epitaxial wafer and electrodes prepared on the epitaxial wafer. AlGaN-based ultraviolet LED epitaxial wafers generally include: a substrate and a buffer layer, n-type semiconductor layer, active layer, electron blocking layer and p-type semiconductor layer that are epitaxially grown on the substrate in sequence. When a current is injected into the AlGaN-based ultraviolet LED, the electrons injected into the n-type semiconductor layer and the holes injected into the p-type semiconductor layer will enter the multi-quantum well active region under the action of the current and recombine to emit ultraviolet light. Among them, the electron blocking layer is generally an AlGaN electron blocking layer with a hi...

AI Technical Summary

Problems solved by technology

[0004] In order to solve the problem that electrons are easy to escape from the active area and holes are not easy to inject into the active area in the ultraviolet LED device, resulting in low luminous efficiency of the ultraviolet LED device, the inventor thought of improving the structure of the electron blocking layer on the ultraviolet LED epitaxial wafer, To provide a specially structured electron blocking layer with a higher conduction band energy level and a smaller valence band energy level, thereby effectively improving the radiative recombination efficiency of electrons and holes in the active region and improving the luminous efficiency of ultraviolet LED devices

Images