Method for growing LED epitaxial structure

Abstract

The invention provides a method for growing an LED epitaxial structure, which includes the process of growing a GaN medium-temperature low-pressure buffer layer and a three-dimensional structure layer. The method specifically includes the following steps: S2, growing a GaN medium-temperature low-pressure buffer layer; and S3, growing a three-dimensional structure layer. The three-dimensional structure layer includes a 3D-like thin layer, a 3D thick layer and a 3D healing layer grown in turn from bottom to top. The step S3 of growing a three-dimensional structure layer includes the following sub-steps: S3.1, growing a 3D-like thin layer; S3.2, growing a 3D thick layer, which is a silicon-doped GaN layer; and S3.3, growing a 3D healing layer. The lattice mismatch can be improved, the dislocation defect can be reduced, and the light output power, anti-aging ability and anti-static ability of LED devices can be improved.

Description

technical field [0001] The invention relates to the technical field of LEDs, in particular to a method for growing an LED epitaxial structure. Background technique [0002] In the process of growing LED epitaxial structures on the substrate by using the metal chemical vapor deposition method MOCVD in the traditional LED epitaxial structure growth method, point dislocations, ductile dislocations and helical dislocations often occur due to the lattice mismatch between the substrate and GaN. Growth defects of dislocations. Generally speaking, the dislocation density of GaN grown by MOCVD method is 1×10 10 ~3×10 10 piece / m 2 , Dislocation defects severely damage the original crystal order of gallium nitride, thereby reducing the light output power of LED devices. For example, screw dislocations extend from the bottom layer of the LED epitaxial structure to the surface of the LED epitaxial structure, and pass through the LED light-emitting layer. Screw dislocations lead to no...

AI Technical Summary

Problems solved by technology

Generally speaking, the dislocation density of GaN grown by MOCVD method is 1×10 10 ~3×10 10 piece / m 2 , Dislocation defects severely damage the original crystal order of gallium nitride, thereby reducing the light output power of LED devices. For example, screw dislocations extend from the bottom layer of the LED epitaxial structure to the surface of the LED epitaxial structure, and pass through the LED light-emitting layer. Screw dislocations lead to non-luminescent radiation of holes and electrons in the LED light-emitting layer, which reduces the light output power of the LED device

In addition, dislocation defects will also increase the leakage channels of LED devices, which will accelerate the aging of LED devices due to the increase in leakage channels. Dislocation defects will also increase the breakdown path of LED devices and cause LED antistatic capabilities to weaken

At present, the LED market requires low driving voltage for LED chips, especially under high current density, the smaller the driving voltage and the higher the light efficiency, the better, but the current density is too high. The ability to expand the current is limited, and it is very easy to cause damage to the LED device, which eventually leads to a decrease in the anti-aging ability and anti-static ability of the LED device

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