Method for reworking metal layer

Abstract

The invention provides a method for reworking a metal layer, which is applied in the field of integrated circuit manufacture. The method comprises the following steps: carrying out chemical mechanical lapping treatment on the metal layer, and removing a waveform structure and partial metal from the surface of the metal layer to form a globally planarized metal layer; depositing a passivation layer on the metal layer; and carrying out chemical mechanical lapping treatment on the structure, and removing the passivation layer and partial metal to form a planarized metal layer. The method for reworking the metal layer can greatly reduce surface defect caused by a normal chemical mechanical lapping process, such as the defects of metal, chemical, grinding fluid residue, microparticle residue and the like, even metal surface corrosion and crater defect, can remarkably improve the defect after the chemical mechanical lapping process, and increase the rate of good products.

Description

technical field [0001] The invention relates to the field of semiconductor product manufacturing, and in particular to a rework method applied in a chemical mechanical grinding process. Background technique [0002] The first time chemical mechanical polishing (CMP) was used in an interconnect process was in the planarization process of tungsten plug (WPlug) for Al interconnects. However, as the size of the device decreases and the structure becomes more and more complex, the disadvantages of aluminum wires become more and more obvious, including the increase of response delay (characterized by RC). Because copper has good electrical conductivity and excellent electromigration properties, copper interconnects have gradually replaced aluminum interconnects, and copper chemical mechanical polishing (CuCMP) has gradually attracted the attention of the industry. Generally, the copper damascene structure includes a semiconductor substrate, a dielectric layer is deposited on the ...

AI Technical Summary

Problems solved by technology

The existing heavy industry technology is very easy to cause metal surface erosion and metal damage when removing the above defects, and brings more corrosion and metal damage defects while removing the original defects. Therefore, the risk of heavy industry failure is very high, and chips are often scrapped , the effect is very unsatisfactory (please refer to Figure 1a and Figure 1b , Figure 1a and Figure 1b Shown is a comparison of defect effects on wafers processed by prior art rework methods), so there is an urgent need for a rework method that can minimize the risk of rework wafers

Images