Ultraviolet LED element and fabricated method of AlGaN base sapphire substrate

Abstract

The invention discloses an ultraviolet LED element and a fabricated method of AlGaN base sapphire substrate, relates to the technical field of microelectronics and mainly solves the problem of low emergent light efficiency. The ultraviolet LED element comprises a low-temperature AlN nucleating layer, a high-temperature AlN nucleating layer, an intrinsic AlGaN epitaxial layer, an n-AlGaN barrier layer, an active zone, a p-AlGaN barrier layer, a low Al component p-type AlGaN layer, a p-type GaN cap layer, and a window zone arranged at the p-type GaN cap layer, which are sequentially arranged from top to bottom. The ultraviolet LED element etches the p-AlGaN cap layer until the p-AlGaN with low Al component by a drying method to form the column emergent light window, and then etches the p-AlGaN cap layer until the p-AlGaN with low Al component by a wetting method so as to change the column emergent light window into a similar hemispheric window, can make the material surface of the window be coarsened while increasing the emergent pore diameter of the window, and greatly improves the power and the efficiency of emergent light. The invention has simple process, good repetitiveness and high reliability, and can be used to occasions of water treatment, medical treatment and biomedicine, and the white light illumination.

Description

technical field [0001] The invention belongs to the technical field of microelectronics and relates to a semiconductor device, in particular to a method for realizing a novel AlGaN-based multi-quantum well uv-LED device, which can be used in the fields of water treatment, medical treatment, biomedicine and white light illumination. Background technique [0002] As an outstanding representative of the third-generation semiconductor materials, III-V compound semiconductor materials have many excellent characteristics, especially in optical applications. The alloy {Ga(Al,In)N} composed of Ga, Al, In, N Can cover the entire visible light region and near ultraviolet light region. Moreover, the group III nitrides with wurtzite structure have direct band gaps, which are very suitable for the application of optoelectronic devices. Especially in the ultraviolet region, the AlGaN-based multi-quantum well uv-LED has shown great advantages, and has become one of the hot spots in the de...

AI Technical Summary

Problems solved by technology

In 2004, a 250nm LED was produced. The maximum power of a 200μ×200μ chip is close to 0.6mW, but the external quantum efficiency is only 0.01%.

As the emission wavelength decreases, the bottom buffer layer absorbs more and more ultraviolet light, which seriously affects the output light power and external quantum efficiency.

At present, the quality of the epitaxial layer is mainly improved by improving the structure of the device. However, the existing technology of emitting light from the bottom still has great shortcomings. The external quantum efficiency is too low; the second is that the crystal quality of the bottom AlN buffer layer is poor, resulting in an increase in the non-radiative recombination center of the material, which absorbs more ultraviolet light; the third is that the bottom buffer layer captures photons under the action of electrical stress. Defects increase, seriously affecting the reliability of the device

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