Method for removing air bubble area in bonding process

Abstract

The invention relates to a method for removing a bubble region in a bonding process. The method comprises the following steps of (a) bonding and fixing a surface wafer and a substrate wafer; (b) determining the position of the bubble region; (c) thinning the back surface of the surface wafer to a required thickness so as to obtain a thin wafer; (d) arranging cutting line mask layer on the above thin wafer, and obtaining a cutting line window passing through the cutting line mask layer, wherein the cutting line window is at least arranged above a cutting line corresponding to an outer ring of the bubble region; (e) etching the cutting line corresponding to the outer ring of the bubble region by using the above cutting line window to remove the cutting line corresponding to the outer ring of the bubble region; and (f) removing the above cutting line mask layer, and removing the thin wafer corresponding to the bubble region after positioning. The method is simple in process step, is compatible with the traditional process step, is wide in application range and is safe and reliable, the bubble region in the bonding process can be effectively removed, and the utilization rate and the finished rate of the wafer are improved.

Description

technical field [0001] The invention relates to a process method, in particular to a method for removing bubble regions in a bonding process, and belongs to the technical field of semiconductors. Background technique [0002] With the development of semiconductor technology, the feature size of integrated circuits continues to shrink, and the interconnection density of devices continues to increase. Therefore, wafer-level packaging (Wafer Level Package, WLP) has gradually replaced wire-bonding packaging and has become a more commonly used packaging method. Wafer Level Packaging (WLP) technology is a technology that performs packaging and testing on the entire wafer and then cuts it to obtain a single finished chip. Requirements for lightness, smallness, shortness, thinning and low price. [0003] Wafer-level packaging, whether using MEMS or CIS BSI process, requires bonding, including permanent bonding and temporary bonding. Permanent bonding processes are generally divid...

AI Technical Summary

Problems solved by technology

[0004] However, in the bonding process, due to unstable process or unclean wafer surface, it is easy to cause bubbles on the wafer bonding surface

Once bubbles are formed, in the subsequent thinning of the wafer, the area will form a bulge, and it is very easy to break, and even the entire wafer will be broken, polluting the machine, and causing the wafer to be scrapped

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