Method of forming a metal wiring in a semiconductor device

Abstract

A method of forming a metal wiring in a semiconductor device. In order to overcome the limitation of copper filling into the damascene pattern formed on an insulating film using copper as a metal wiring, a chemical enhancer layer is formed on the damascene pattern which is then filled with copper by depositing copper by means of MOCVD method using a copper precursor. The chemical enhancer is exposed to a plasma process or radical plasma process so that it remains only within a bottom portion of the damascene pattern. Therefore, a selective copper deposition within the damascene pattern is provided to accelerate the deposition speed of copper by CECVD method, thus overcoming the limitation of slow and incomplete copper filling for ultra-fine structures.

Description

[0001] 1. Technical Field[0002] A method of forming a metal wiring in a semiconductor device is disclosed. More particularly, the present invention relates to a method of forming a metal wiring in a semiconductor device by which a chemical enhancer layer is formed and copper filled in the damascene pattern by means of selective deposition method using a copper precursor to form a copper wiring.[0003] 2. Description of the Prior Art[0004] As the size of a contact is reduced and the aspect ratio is increased for rapid high performance of next-generation semiconductor devices, a metal wiring using aluminum has a problem in that the EM characteristic in which the lifetime of the metal wiring is shortened due to high current density. In order to overcome this problem, a study has been made on a wiring material having low resistance. Recently, wiring material using copper (Cu) has been studied. Also, the commercialization of electroplating method considering cost and deposition speed has ...

AI Technical Summary

Benefits of technology

[0006] A method of forming a metal wiring in a semiconductor device is disclosed that is capable of performing a selective deposition process of copper using a copper precursor and thus easily forming a copper wiring in an ultra-fine texture, by performing a chemical enhancer accelerating deposition of copper and then performing a plasma process or a radical plasma process to remain the chemical enhancer layer only at the bottom of the damascene pattern.

Problems solved by technology

As the size of a contact is reduced and the aspect ratio is increased for rapid high performance of next-generation semiconductor devices, a metal wiring using aluminum has a problem in that the EM characteristic in which the lifetime of the metal wiring is shortened due to high current density.

As the electroplating method, however, has a limitation in filling in case of ultra-fine structure, interest in a copper wiring filling using a CVD method has been generated.

The CVD method has a low efficiency due to a low deposition speed and cost, when compared with a wiring filling by means of electroplating method, but there has an effort to overcome this problem by introducing a new process method.

This CECVD method, however, still has the problems of uniformly spraying a chemical enhancer and an inability to distribute the chemical enhancer into a desired position for a selective copper filling process.

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