Anti-corrosion method for the back of a single-sided polished wafer

Abstract

The invention discloses an anti-corrosion method for the back of a single-sided polished wafer. Step S1 is adopted: adding a reducing agent to the substrate, and the reducing agent covers the back of the wafer to prevent the chemical reaction between the polishing liquid and the back of the wafer. The method provided by the invention can not only significantly reduce the backside corrosion ratio of the wafer in the single-side polishing process, but also ensure that the production efficiency and production cost are not affected.

Description

technical field [0001] The invention relates to the technical field of wafer processing, in particular to an anti-corrosion method for the back surface of a single-side polished wafer. Background technique [0002] In the process of using the substrate to perform single-sided rough polishing and fine polishing of the wafer, a certain proportion of back corrosion marks will inevitably be produced, and the degree of corrosion directly determines the amount of damage required for repair (generally above 15um). It has a serious impact on the wafer polishing process. If the backside corrosion is serious, it is likely to cause batch scrapping. Causes of backside corrosion of single-sided polished wafers in the prior art, combined with figure 1 and figure 2 , figure 1 and figure 2 Middle is a schematic diagram of the structure of the polishing device for polishing the wafer 3 . The working disk 1 is used for loading and unloading or pasting the substrate 2, and the material ...

AI Technical Summary

Problems solved by technology

Then the back side of the wafer 3 is corroded, causing the back side of the single-sided polished wafer to be corroded

[0003] The prior art is to achieve the effect of isolating the back of the wafer from the liquid medicine by changing its processing method (such as reducing the polishing time, etc.) or increasing the protective film (such as attaching a protective film on the back of the polished wafer), so as to completely eliminate Produces crystal backside etching, but is inefficient and expensive

Although the elimination rate of this kind of defect can reach 100%, but the investment is large, and it will cause the increase of other types of defects, which has no obvious contribution to the overall pass rate, and has no cost and efficiency advantages

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