Method for improving electromigration reliability of metal connection wire

Abstract

The invention provides a method for improving electromigration reliability of a metal connection wire. The method comprises the steps of providing a semi-conductor substrate, depositing a first medium layer on the semi-conductor substrate, and forming a first metal layer in the first medium layer through the single Damascus technology; depositing a first barrier layer on the first medium layer, forming a groove through etching, and exposing a the first metal layer; forming a first metal protective layer and filling the groove with the first metal protective layer; depositing a second medium layer, and forming a second metal layer on the second medium layer through the second Damascus technology; then forming a second metal protective layer and a sub-sequent metal layer and metal protective layer. The metal layers are covered with the metal protective layers to effectively improve adhesiveness of the surfaces of metal, particularly adhesiveness of the surface of copper, the diffusion phenomenon at the interface position of the upper surface of the metal and the barrier layer is depressed, and electromigration reliability of the metal connection wire can be effectively improved.

Description

technical field [0001] The invention relates to the field of semiconductor integrated circuits and its manufacture, in particular to a method for improving the reliability of electromigration of metal wiring. Background technique [0002] With the development of VLSI technology, the feature size is continuously reduced, and the chip integration is getting higher and higher, which leads to a sharp increase in the current density on the metal connection, and the power consumption per unit area of ​​​​the chip increases. Therefore, the reliability of the metal connection Resilience has always been an important issue in the field of integrated circuit manufacturing. [0003] In the process of 45nm and below, in order to reduce the delay of back-end interconnection RC (R refers to resistance, C refers to capacitance), the copper / low dielectric constant dielectric (low-k dielectric) system gradually replaces the traditional aluminum / silicon dioxide system as the industry mainstre...

AI Technical Summary

Problems solved by technology

[0006] The purpose of the present invention is to provide a method to improve the reliability of electromigration of metal wiring, solve the interface diffusion phenomenon between the copper upper surface and the dielectric covering layer, and improve the problem of copper electromigration failure

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