A kind of manufacturing method of vertical structure deep ultraviolet LED chip

Abstract

The invention discloses a method for manufacturing a vertical structure deep ultraviolet LED chip. Specifically: the p-GaN ohmic contact layer is processed into a grid structure by laser direct writing process, and a high-reflectivity p-type low-resistance ohmic contact Ni / Al electrode is used for ohmic contact with the p-GaN grid , forming a good ohmic contact. Then, the honeycomb structure is obtained by etching the groove array and the inner mirror groove array between the Ni / Al p electrode conductive layer and the n-AlGaN layer of the epitaxial layer, and the Al layer is deposited as a mirror in the inner mirror groove side walls, thereby obtaining a honeycomb internal reflector structure. By replacing the p-GaN layer in the traditional deep-UV LED with a grid-shaped transparent p-GaN layer and designing a honeycomb internal reflector structure, the emission of photons propagating laterally in the active layer of the LED is realized, reducing the amount of time in the deep-UV LED chip. The loss of the active area greatly improves the light extraction efficiency of the chip.

Description

technical field [0001] The invention belongs to the technical field of semiconductor light emitting devices, in particular to a method for manufacturing a vertical structure deep ultraviolet LED chip. Background technique [0002] As a new type of high-efficiency solid-state light source, light-emitting diodes (Light Emitting Diodes, referred to as "LED") are widely used in solid-state lighting, transportation, military and medical fields due to their high efficiency, long life, energy saving, environmental protection, and rich colors. . With the gradual maturity of LED technology and the needs of industrialization and marketization, there are stricter requirements on the luminous efficiency and other properties of LED devices. As a branch of LED, ultraviolet LED can not illuminate but has all the advantages of LED. In theory, it can replace all traditional ultraviolet light sources, which greatly expands the application field of LED. The most common ultraviolet rays mainl...

AI Technical Summary

Problems solved by technology

[0005] Although deep UV LEDs are more cost-effective and environmentally friendly than UV lamps, they cannot easily replace UV lamps due to their low light output

Due to the low light extraction efficiency (LEE) and high epitaxial crystal defects in AlGaN-based deep ultraviolet LED chips, their light output power and external quantum efficiency (EQE) are low

As the emission wavelength decreases, the transverse magnetic (TM) polarized light propagating parallel to the c-plane of sapphire accounts for the main part, and the propagation path from the multi-quantum well is longer, and the light loss is larger, resulting in a decrease in light extraction efficiency, and at the same time, the high resistance The AlGaN layer and the current crowding phenomenon caused by the tilt angle inside the chip will also affect the propagation of TM polarized light

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