Graphite bearing disc used for production process of LED epitaxial wafer

Abstract

The invention discloses a graphite bearing disc used for a production process of an LED epitaxial wafer. The graphite bearing disc comprises a plurality of wafer grooves formed in the bearing disc, wherein the wafer grooves are used for containing epitaxial wafer substrates. The graphite bearing disc is characterized in that a convex part structure is arranged on a central region of the bearing disc so that the vortex area of the central region of the bearing disc in an epitaxial production process can be reduced, and the problem that the light intensity of a partial region, which is formed towards the center of a shaft of the bearing disc, of the epitaxial wafer of an inner ring is low can be solved; and therefore, the brightness uniformity of the inner ring is improved and the whole uniformity of the brightness of the epitaxial wafers of the inner and outer rings is improved.

Description

technical field [0001] The invention belongs to the technical field of semiconductors, and in particular relates to a graphite carrier plate used in an LED epitaxial wafer manufacturing process. Background technique [0002] Light Emitting Diode (English for Light Emitting Diode, referred to as LED) is a solid-state semiconductor diode light-emitting device, which is widely used in lighting fields such as indicator lights and display screens. [0003] At present, LED epitaxial wafers (or epitaxial wafers) are generally obtained by Metal-organic Chemical Vapor Deposition (Metal-organic Chemical Vapor Deposition, MOCVD in English), and the process is generally: the epitaxial wafer substrate (such as sapphire Substrate) is put into the groove of the graphite carrier (Wafer carrier in English), and together with the graphite carrier, it is introduced into the MOCVD reaction chamber. Organometallic compounds and III-V gases are repolymerized on the wafer substrate after pyrolys...

AI Technical Summary

Problems solved by technology

Using a traditional MOCVD reaction chamber to grow LED epitaxial wafers, such as figure 2 As shown, because the high-speed rotating airflow sprayed downward from the top cover will generate a certain thermal buoyancy convection at the center of the graphite carrier plate, forming a vortex 102 in a local area, causing the inner ring of the epitaxial wafer (with the flat side of the substrate facing the carrier) Take the center of the disk as an example) the dislocation density of tiny Pits in the area of ​​about 0-20 mm near the flat edge increases, and the half-width of the XRD (002) plane and XRD (102) plane is larger than the central area of ​​the epitaxial wafer, causing the local The non-radiative recombination luminescence in the area becomes larger, and the luminous intensity is low (down about 40~60%), which leads to the uneven brightness of the epitaxial wafers in the inner circle.

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