Manufacturing method of deep ultraviolet LED chip with vertical structure

Abstract

The invention discloses a manufacturing method of a deep ultraviolet LED chip with a vertical structure. The method is specifically characterized in that a p-GaN ohmic contact layer is processed intoa grid-shaped structure by using a laser direct writing process, and a p type low-resistance ohmic contact Ni / Al electrode with high reflectivity is used for ohmic contact with the p-GaN grid to formgood ohmic contact; a groove array and an inner reflector groove array are etched between a Ni / Al p electrode conductive layer and the n-AlGaN layer of an epitaxial layer to obtain a honeycomb structure, and the Al layer as a reflector is deposited on the side wall of the inner reflector groove to obtain a honeycomb-shaped inner reflector structure; and by replacing a p-GaN layer in a traditionaldeep ultraviolet LED with the grid-shaped transparent p-GaN layer and designing the honeycomb-shaped inner reflector structure, emission of photons transversely propagated on the LED active layer is achieved, loss of a source region in the deep ultraviolet LED chip is reduced, and the light extraction efficiency of the chip is greatly improved.

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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