A kind of preparation method of epitaxial wafer of light-emitting diode

Abstract

The invention discloses a preparation method of an epitaxial wafer of a light emitting diode, and belongs to the field of manufacturing of light emitting diodes. A plurality of substrates grown with an AlN layer are placed in a circular groove distributed on a plurality of concentric circles in the MOCVD device, and the thickness of a GaN nucleation layer grown on the AlN layer is controlled to reduced with increasing of the diameters of the concentric circles. With the increasing of the diameters of the concentric circles, the thickness of the GaN nucleation layer is gradually reduced, the surface of the GaN nucleation layer in the circular groove can be changed from a state of depressing towards the bottom surface of the circular groove to a state of bulging upwards far away from the bottom surface of the circular groove, and the change trend is opposite to the change trend of the warping generated at the surfaces of the substrates so that the surface of the GaN nucleation layer is complete, the surface warping of the GaN nucleation layer and the surface warping of the substrate are mutually offset and the heat transmitted to an InGaN / GaN multiple quantum well layer is relativelyuniform to improve the uniformity of the light-emitting wavelength of the InGaN / GaN multiple quantum well layer so as to improve the light-emitting qualified rates of the epitaxial wafers obtained inthe same batch.

Description

technical field [0001] The invention relates to the field of light-emitting diode manufacturing, in particular to a method for preparing an epitaxial wafer of a light-emitting diode. Background technique [0002] Light-emitting diodes are semiconductor diodes that can convert electrical energy into light energy. They have the advantages of small size, long life, and low power consumption. They are currently widely used in automotive signal lights, traffic lights, display screens, and lighting equipment. The epitaxial wafer is the basic structure for making light-emitting diodes. The structure of the epitaxial wafer includes a substrate and an epitaxial layer grown on the substrate. Among them, the structure of the epitaxial layer mainly includes: AlN layer, GaN nucleation layer, undoped GaN layer, N-type GaN layer, InGaN / GaN multiple quantum well layer and P-type GaN layer grown on the substrate in sequence. [0003] When the current epitaxial layer is grown, metal-organic ...

AI Technical Summary

Problems solved by technology

The centrifugal force on the substrate in the circular grooves of each circle is different, which will cause the surface of the substrate on the concentric circles with a smaller diameter to bulge upwards away from the bottom surface of the circular grooves, and the surface of the concentric circles with a larger diameter will bulge upwards. The surface of the substrate is sunken downward toward the bottom of the groove in the center of the circle, and the substrate on the turntable is warped to varying degrees

In addition, due to the warping of the substrate and the epitaxial layer, the heat transferred to the InGaN / GaN multi-quantum well layer will be uneven, which will affect the distribution of In in the InGaN / GaN multi-quantum well layer, thereby affecting the InGaN / GaN multi-quantum well layer. The uniformity of the luminous wavelength, so this setting will eventually make the uniformity of the InGaN / GaN multi-quantum well layer in the epitaxial wafers obtained in the same batch vary greatly, which will affect the luminous pass rate of the epitaxial wafers obtained in the same batch

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