A method of improving the degree of wafer bonding

Abstract

The present invention relates to the field of semiconductors, in particular to a method for improving wafer bonding, comprising: annealing the silicon nitride film to form a metal layer, covering the surface of the silicon nitride film, and patterning the metal layer , to form a metal grid on the surface of the silicon nitride film, and when patterning the metal layer, remove the silicon nitride film located under the removed part of the metal layer, so as to form a metal grid on the metal layer The oxide layer is exposed between the grids. The method of the present invention forms a silicon nitride film, after the silicon nitride film is annealed, the hydrogen ions in the silicon nitride film can be fully bonded with the dangling bonds of the silicon atoms at the interface of the silicon substrate, reducing the silicon substrate The number of dangling bonds is medium, the degree of wafer bonding is improved, and the process of etching silicon nitride film before the formation of the metal grid in the traditional process is removed, and the silicon nitride film under the removed part of the metal layer is removed during the metal grid process. To achieve the purpose of simplifying the process.

Description

technical field [0001] The invention relates to the field of semiconductors, in particular to a method for improving the degree of wafer bonding applied to the preparation process of image sensor devices. Background technique [0002] During the wafer manufacturing process, active dangling bonds are formed at the silicon interface due to the absence of silicon atoms and the presence of unbonded electrons on the interface silicon atoms. Increasing the degree of reconciliation of dangling bonds between the wafer boundaries is beneficial to improving device performance. Due to the low degree of dangling bonds between the silicon interfaces, there are fewer sources of yards to form bonds with the dangling bonds between the silicon interfaces, and there is a lack of bonding power, which adversely affects the device performance. In the prior art, the bonding of dangling bonds between silicon interfaces is improved by depositing a SiN layer, annealing the SiN layer, and etching to...

AI Technical Summary

Problems solved by technology

Due to the low degree of dangling bonds between silicon interfaces, there are fewer sources of bonding with dangling bonds between silicon interfaces and lack of bonding power, which adversely affects device performance

In the prior art, the bonding of the dangling bonds between the silicon interfaces is improved by depositing the SiN layer, annealing the SiN layer, and etching to remove the annealed SiN layer to improve the performance of the device, but the process is complicated

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