Wafer full laser dicing method

Abstract

The invention discloses a method for laser full cutting of a wafer, comprising the following steps: A. calibrating and measuring the center of gravity of the wafer; B. loading the wafer according to the center of gravity determined in step A; C. The adsorption position of the wafer is detected and positioned; D, the cooling liquid is evenly coated on the surface of the wafer; E, the laser is used to draw a cutting groove on the surface of the wafer, and the depth of the cutting groove is 10 μm ~ 15 μm; F 1. Homogenize the coolant on the surface of the wafer again; G. Adjust the parameters of the laser, and shape the laser beam at the same time, so that the laser beam has a blade, and use the blade to cut the wafer along the cutting groove. The beneficial effects of the present invention are: the present invention realizes the direct cutting of the wafer by adopting the laser full cutting mode, greatly reduces the problem of its fragmentation rate; greatly improves the production efficiency; increases the number of chips that can be produced in the wafer; reduces the laser The influence of the thermal effect brought by cutting.

Description

technical field [0001] The invention relates to a wafer processing method, in particular to a wafer laser cutting method. Background technique [0002] Wafers are widely used in the chip industry. During the processing of chips, wafers need to be divided. At present, the wafer segmentation method is realized by loading, cutting, cleaning / drying, and the cutting is achieved by single-spindle or opposed double-spindle, parallel double-spindle grinding wheel blades to groove and then cut, or The laser is used to slot first and then the grinding wheel blade to cut. But the whole cutting process is always inseparable from the diamond grinding wheel blade; as the size of the wafer develops from 4 inches, 6 inches, 8 inches to 12 inches, its size continues to increase, and the thickness correspondingly changes from the original 300μm, 200μm, From 150 μm to the current 100 μm and 75 μm, the thickness is constantly decreasing. [0003] However, for grinding wheel blade cutting, th...

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Problems solved by technology

[0004] Moreover, with the background of high integration such as SiP (System in Package), high flexural strength sheet manufacturing technology is becoming more and more important, and wafers with a thickness of less than 100 μm will gradually become the mainstream. Blades cannot be directly used for cutting such thin wafers; and the low dielectric constant (Low-k) film and copper materials that are gradually adopted on high-speed electronic components are difficult to cut with ordinary diamond grinding wheel blades, sometimes It cannot meet the processing standards required by electronic component manufacturers. Compound semiconductors such as GaAs (gallium arsenide), GaN (gallium nitride), and GaP (gallium phosphide) used in high-frequency electronic components are cut with diamond grinding wheel blades. However, in the existing technology, although the laser cutting technology is used to replace the traditional diamond grinding wheel blade cutting, it still needs to be split after laser cutting in order to truly realize the cutting of the wafer. Segmentation, which improves the yield rate to a certain extent, but the efficiency is still not high

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