Manufacturing method of sapphire substrate with identifiable front side and back side

Abstract

The invention relates to a manufacturing method of a sapphire substrate with an identifiable front side and back side. According to the manufacturing method, lead angles with different lengths or angles are ground at a side connecting surface of the sapphire substrate, or different curvature radii are ground at the connecting surfaces of cambered surfaces on the left and right sides of the sapphire substrate and a plane, so that the difference is generated on two sides of the sapphire substrate and the front side and the back side of the sapphire substrate can be identified by a worker in a naked eye or try touch mode.

Description

Technical field [0001] The present invention relates to a method for manufacturing a sapphire substrate, in particular to a method for manufacturing a sapphire substrate whose front and back sides can be identified. Background technique [0002] The composition of Sapphire is alumina (Al 2 O 3 ) Is the main substrate material for preparing gallium nitride (GaN) epitaxial light-emitting layers, and gallium nitride can be further used to make ultra-high-brightness blue, green, blue-green, white LED and other electronic components. [0003] In the manufacture of sapphire substrates, sapphire single crystal ingots are cut, which must be processed by rounded edges and multiple grinding and polishing processes. These processes will affect the warpage of the substrate. This warpage The degree of quality control is closely related to the yield rate of the yellow etching and epitaxial process in the later stage. [0004] Since the sapphire substrate is polished, it must be processed by wax b...

AI Technical Summary

Problems solved by technology

[0006] Due to the difference in the axial direction of the sapphire substrate, the process is also affected by the determination of the processing surface

More precisely, the lattice positions of the C-axis and M-axis sapphire substrates are symmetrical, while the lattice positions of the R-axis sapphire substrate are asymmetrical, and the position of the flat side of the R-axis sapphire substrate is C-axis The counterclockwise 45° position of the sapphire substrate, so if the front and back sides are wrongly distinguished and turned over, the direction of the characteristic axis will be reversed, which will affect the epitaxy parameters and film quality of the later stage

[0007] In addition, in the polishing process, if the R-axis wafer misjudges the processing surface in the single-side polishing part, the axial variation of the characteristics will cause epitaxy parameters and film quality variations, thereby reducing the epitaxy yield.

C-axis and M-axis wafers may cause yield loss due to misjudgment of the processing surface, such as not being able to distinguish which surface the wax is on

In addition to the part of double-sided polishing, based on the different polishing parameters and warpage of the two sides, if the front and back sides are not defined before entering the grinding and polishing process, there may be misjudgment or misjudgment during the personnel judgment or processing. The situation of wrong surface processing occurs

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