Method for chemical mechanical polishing and forming method of metal interconnection layer

Abstract

The present invention provides a method for chemical mechanical polishing, comprising the steps of: supplying a wafer, wherein the wafer surface is provided with a metal layer; decreasing reactions between deionized water spray and the wafer surface; polishing the wafer surface to remove spare parts of the metal layer. Correspondingly, the present invention further provides a forming method of a metal interconnection layer. The step of decreasing reactions between deionized water spray and the wafer surface is performed before the wafer surface is polished, so that the method for chemical mechanical polishing and the forming method of metal interconnection layer can prevent the deionized water from contaminating on the metal layer of the wafer surface and prevent the deionized water from reacting with the metal layer to generate oxides; therefore, shortages of pits or spots at the wafer surface can be eliminated basically after the chemical mechanical polishing (CMP) process, and the reliability of integrated circuit is ensured.

Description

technical field [0001] The invention relates to the technical field of semiconductor manufacturing, in particular to a chemical mechanical polishing method and a method for forming a metal interconnection layer. Background technique [0002] With the increasing demand for high integration and high performance of ultra-large-scale integrated circuits, semiconductor technology is developing towards technology nodes with 65nm or even smaller feature sizes, and the computing speed of chips is obviously affected by the resistance capacitance delay (Resistance Capacitance) caused by metal wires. Delay Time, RC Delay Time). Therefore, in the current semiconductor manufacturing technology, copper metal interconnection with lower resistivity is used to replace the traditional aluminum metal interconnection, so as to improve the phenomenon of RC delay. [0003] Due to the low resistivity of copper, devices using copper as interconnection wires can withstand denser circuit arrangement...

AI Technical Summary

Problems solved by technology

[0006] However, the problem is that in the actual production process, after the above-mentioned chemical mechanical polishing process, defects such as pits or spots often appear on the wafer surface, such as figure 1 As shown, these pits or spot defects 2 on the surface of the wafer 1 may cause a series of problems such as short circuit of the metal interconnection layer, thereby affecting the reliability of the integrated circuit

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