Epitaxial growth method for improving inner quantum efficiency of GaN-based LED

Abstract

The invention relates to an epitaxial growth method for improving the inner quantum efficiency of a GaN-based LED, belonging to the technical field of semiconductors. The method comprises the following steps of: alternately inputting ammonia gas as well as Group III metal organic source materials of gallium and indium in a growth reaction chamber in a pulsing way during the growth of an In-Ga-N quantum well layer of a GaN-based blue / green light LED active area; and forming a In-Ga-N quantum well luminous layer with high luminous efficiency in a modulation growth process under a set duration, a set interval and a set pulse period. The method can weaken an internally-built electric field of the In-Ga-N / GaN quantum well, improve the quantum localization effect, enhance the radiative recombination rate and increase the inner quantum efficiency of luminescence so as to improve the luminous efficiency and the brightness of the LED. The method is suitable for the MOCVD (Metallo Organic Chemical Vapor Deposition) epitaxial growth of a nitride-based blue / green light LED epitaxial material with high brightness and high luminous efficiency.

Description

technical field [0001] The invention belongs to the technical field of semiconductors, in particular to an epitaxial growth method for improving the internal quantum efficiency of gallium nitride-based blue light / green light emitting diodes. Background technique [0002] Gallium Nitride (GaN) is the third generation direct energy gap wide bandgap semiconductor with a bandgap width of 3.39eV. GaN-based green and blue light-emitting diodes (LEDs) have the advantages of high brightness, low energy consumption, long life, and fast response, and are widely used in full-color display, signal indication, and landscape lighting. In particular, the research and development of white LEDs made of GaN-based blue LEDs mixed with phosphors is progressing rapidly. The emission wavelength of white LEDs is only in the visible light region, which avoids the strong infrared radiation of incandescent lamps and can save a lot of energy. At the same time, white LEDs are small in size, long in li...

AI Technical Summary

Problems solved by technology

Because there is usually a large lattice constant mismatch and thermal expansion coefficient difference between nitride and sapphire substrates, there are many crystal defects in the nitride epitaxial layer grown by metal organic chemical vapor deposition (MOCVD) epitaxy, such as Dislocations, etc., the crystal quality of the material is greatly affected

In particular, due to the polarization effect caused by stress caused by lattice mismatch, there is a large electric field in the quantum well, which leads to the separation of electron and hole wave functions in space, reduces the radiation recombination efficiency, and reduces the internal quantum efficiency and brightness of luminescence.

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