Mask plate and exposure method

Abstract

The invention provides a mask plate and an exposure method. The mask plate comprises a first mask pattern and a second mask pattern which are complementary, wherein the first mask pattern comprises aplurality of first strip-shaped patterns extending along a first direction; the second mask pattern comprises a plurality of second strip-shaped patterns extending along a second direction; the firstdirection is crossed with the second direction; in the exposure method, the first mask pattern and the second mask pattern are employed respectively to sequentially execute twice exposure processes onthe LED substrate, so that after alignment overlapping of the formed exposure patterns, a PSS pattern can be generated; compared with a traditional splicing mode, the method has the advantages that the line widths of all the pattern areas are consistent, so that the requirement for image quality is lowered, and an exposure view field does not need to be reduced.

Description

technical field [0001] The invention relates to the technical field of semiconductor manufacturing, in particular to a mask plate and an exposure method. Background technique [0002] Patterned Sapphire Substrate (PSS), that is, a mask for dry etching is grown on the sapphire substrate, a PSS pattern is formed by a standard photolithography process, the sapphire is etched by ICP etching technology, and the mask is removed , and then grow GaN material on it, so that the vertical epitaxy of the GaN material becomes lateral epitaxy, on the one hand, it can effectively reduce the dislocation density of the GaN epitaxial material, thereby reducing the non-radiative recombination of the active region and reducing the reverse leakage current , improve the life of the LED; on the other hand, the light emitted by the active area is scattered by the GaN and sapphire substrate interface multiple times, which changes the exit angle of the total reflection light and increases the probabi...

AI Technical Summary

Problems solved by technology

In the process of making PSS graphics, due to the limited size of the field of view of a single exposure, in order to form the entire piece of PSS graphics, it is necessary to use the method of splicing exposure. The existing method of splicing area division is as follows: figure 1 As shown (orthogonal line division), the stitching line in the figure is a virtual line and will not be actually imaged. The stitching area may need to use 4 exposure fields to complete, such as figure 2 shown

In this solution, the graphic line width of the exposure area at the splicing point will be halved, resulting in higher resolution and higher requirements for image quality, so it is often necessary to reduce the exposure field of view to meet the image quality requirements, but the exposure The exposure efficiency will be greatly reduced when the field of view is reduced

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