Method of processing metal surface in dual damascene manufacturing

Abstract

A processing method for the metal surface in a dual damascene manufacturing is applied to a dual damascene semiconductor structure. The dual damascene semiconductor structure has a metal structure and a spin-on-dielectric (SOD) layer formed on the metal structure, wherein the SOD layer has at least one opening exposing a partial surface of the metal structure. Before the opening is filled, the monoxide on the exposed surface is first removed, then the exposed surface is treated by the plasma at an angle inclined to an axis perpendicular to the exposed surface. The processing method provided in the present invention can avoid the exposed surface being damaged by the plasma and improve the adhesion force between the exposed metal surface and the stuff.

Description

BACKGROUND OF THE INVENTION[0001]1. Field of the Invention[0002]The present invention relates to a method of processing the via in a dual damascene manufacturing. More specifically, the present invention discloses a method of processing the via in a Cu / Spin-on-dielectric (Cu / SOD) dual damascene manufacturing to avoid Cu peeling.[0003]2. Description of the Prior Art[0004]In Cu / SOD dual damascene manufacturing, the major factors to be considered are Cu oxidation and Cu peeling on the bottom surface of the via. Usually the Cu oxidation on the bottom surface of the via can be removed efficiently by using Reactive-Pre-Clean (RPC); on the other hand, the adhesion force between Cu and SOD can be efficiently improved by using Ar plasma treatment.[0005]However, the above-mentioned two procedures cannot match up. If the RPC is performed first, the follow-up Ar plasma treatment will ordinarily increase the via resistance, and then decrease the yield. The drawback of the foregoing order mainly ...

AI Technical Summary

Benefits of technology

The present invention provides a method for treating a metal surface in a semiconductor structure during manufacturing. The method involves using an inclined plasma treatment to reduce damage to the metal surface and prevent electric leakage in the intermetal dielectric layer. This method can improve the adhesion force between the metal surface and the dielectric layer, resulting in a more reliable and efficient semiconductor structure.

Problems solved by technology

However, the above-mentioned two procedures cannot match up.

If the RPC is performed first, the follow-up Ar plasma treatment will ordinarily increase the via resistance, and then decrease the yield.

The drawback of the foregoing order mainly arises from the perpendicular direction of the Ar plasma with respect to the bottom surface of the via in the Ar plasma treatment, therefore damages the Cu surface.

Moreover, Cu on the bottom surface of the via will splash on the side wall of the via and then soon spread into the intermetal dielectric layer and cause the electric leakage of the intermetal dielectric layer.

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