Cutting method of LED chip with no inclined crack angle, optical lens assembly and laser cutting equipment

Abstract

The invention discloses a cutting method based on an LED chip with no inclined crack angle, an optical lens assembly and laser cutting equipment. According to the cutting method, a wafer taking sapphire as a substrate is cut, and the wafer is located on the front surface of the sapphire. The cutting method comprises the following steps that the spot diameter of laser beams emitted by a laser are increased through a beam expander, and then light spots are compressed into a preset diameter through a first adjustable raster; and the laser beams pass through a laser beam shaping lens assembly andare transformed into Bessel ring-type beams, and the Bessel ring-type beams are focused to the back side of the sapphire for cutting vertically. The laser beams emitted by the laser sequentially passthrough the beam expander, the first adjustable raster and the laser beam shaping lens assembly and then are transformed into reduced Bessel ring beams to cut sapphire wafers. The cutting method realizes that the cut LED chip has no inclined crack angle, and meanwhile, the photoelectric property of the LED chip is guaranteed.

Description

technical field [0001] The invention relates to the technical field of laser processing, in particular to a method for cutting an LED chip without an oblique crack angle, an optical lens assembly and a laser cutting device using the optical lens assembly. Background technique [0002] With the development of science and technology, LED chip cutting technology has been widely studied. In traditional LED chip cutting technology, when cutting wafers with sapphire substrate, due to the sapphire lattice, one direction will produce a certain oblique crack. The angle of the oblique crack is different according to the difference of the substrate and the thickness of the wafer substrate. Due to this feature, the traditional cutting method has limitations in the application of MiniLED. MiniLED requires that the direction of the oblique crack angle be cut and its angle is strictly controlled within 1.5 degrees, and the size of the die is smaller than that of the traditional LED chip, ...

AI Technical Summary

Problems solved by technology

[0003] The main purpose of the present invention is to provide a cutting method for LED chips without oblique crack angle, aiming at solving the problem that the oblique crack angle cannot be strictly controlled within 1.5 degrees and the photoelectric characteristics are not damaged during LED chip cutting. technical problem

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