KR20070001552A - Manufacturing method of metal line of semiconductor device - Google Patents

Abstract

A method for manufacturing a metal wire of a semiconductor device is provided to prevent corrosion of the metal wire by performing a H2O plasma process before patterning the metal wire and after removing a photoresist pattern. An interlayer dielectric(30) is formed on a semiconductor substrate having a predetermined lower structure. A metal layer(34) is formed on the interlayer dielectric. A photoresist pattern(36) is formed on the metal layer. The exposed metal layer is photolithographed by using the photoresist pattern as a mask to form a metal wire. The surface of the resultant structure is firstly processed by using H2O plasma. The photoresist pattern is removed. The metal wire is secondly processed by the H2O plasma.

Description

Manufacturing method of metal line of semiconductor device {Manufacturing method of metal line of semiconductor device}

1A to 1D are diagrams illustrating a manufacturing process of a metal wiring of a semiconductor device according to the prior art.

2a to 2d is a process diagram of the metallization of the semiconductor device according to the present invention.

         <Explanation of symbols for the main parts of the drawings>

10, 30: interlayer insulating film 12, 32: barrier metal layer

14, 34 metal layer 16, 36 photosensitive film pattern

18, 38 Cl ions 20 Corrosion residues

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for manufacturing a metal wiring of a semiconductor device, and in particular, to effectively remove residual Cl ions with H2O plasma after etching the metal wiring to prevent the metal wiring from corroding to moisture in the air, thereby improving process yield and device operation reliability. The present invention relates to a metal wiring manufacturing method of a semiconductor device that can be improved.

The recent trend of high integration of semiconductor devices has been greatly influenced by the development of fine pattern formation technology, and the miniaturization of photoresist patterns, which are widely used as masks such as etching or ion implantation processes, are essential in the manufacturing process of semiconductor devices.

The resolution R of this photosensitive film pattern is proportional to the light source wavelength? And the process variable k of the reduced exposure apparatus used, and inversely proportional to the lens aperture (NA, numerical aperture) of the exposure apparatus.

In this case, a method of reducing the wavelength of the light source is used to improve the optical resolution of the reduced exposure apparatus, and a separate thin film capable of using a phase shift mask or improving image contrast as a process method. The C.E.contrast enhancement layer (CEL) method, the three-layer resist method, the silicidation method, etc. which form this on a wafer are developed and used.

In particular, metal wiring used for interconnection of semiconductor devices, power supply, signal transmission, etc., causes metal corrosion at the manufacturing stage, which drastically decreases the lifespan and operation speed of the product, thereby reducing the reliability of the device.

1A to 1D are diagrams illustrating a process of manufacturing metal wirings of a semiconductor device according to the prior art.

First, the interlayer insulating film 10 is coated on a semiconductor substrate (not shown) having a predetermined lower structure and planarized thereon, and then the barrier metal layer 12 and the Al material are formed on the interlayer insulating film 10. The metal layer 14 is formed sequentially.

Thereafter, a photoresist pattern 16, which is a metal wiring mask, is formed on the metal layer 14, and the metal layer 14 and the barrier metal layer 12 which expose the photoresist pattern 16 as a mask are sequentially etched to form a metal. Form the wiring. At this time, a large amount of Cl ions 18 residues remain on the surface of the structure, which is a major cause of metal corrosion. The etching process is performed by using Cl gas, BCl 3 gas for sidewall protection, CHF 3 or N 2 gas, which is a polymer gas. (See FIG. 1A).

Then, before exposing the photoresist pattern 16 to the atmosphere, an H 2 O plasma treatment is performed to convert Cl ions 18 remaining on the wafer into HCl to be removed. At this time, a small amount of Cl ions 18 remain on the wafer and Cl ions 18 remain in the photosensitive film pattern 16. (See FIG. 1B).

Thereafter, the photoresist pattern 16 is removed by O 2 / N 2 plasma to complete the metal wiring of the metal layer 14 pattern and the barrier metal layer 12 pattern. At this time, a small amount of Cl ions 18 remaining in the photoresist pattern 16 or remaining on the wafer surface remains. (See FIG. 1C).

Then, the wafer of the structure is cleaned with a solvent solution, which reacts with moisture in the air according to the time of exposure of the metal wiring in the air to produce a corrosion residue 20. (See FIG. 1D).

In the method of manufacturing a metal wiring of the semiconductor device according to the prior art as described above, H 2 O plasma treatment is performed after the metal wiring patterning, but since Cl ions remain in the photoresist pattern, it is difficult to completely remove Cl ions and remove Cl ions in situ. Even though the removal of Cl ions is greatly influenced by the process conditions and the environment, it is difficult to secure uniformity of the process, which makes it difficult to effectively prevent corrosion of metal wiring.

The present invention is to solve the above problems, an object of the present invention is to effectively perform the H2O plasma treatment after the metal wiring patterning to prevent the occurrence of corrosion even if the metal wiring is exposed to the atmosphere by leaving no Cl ions residues. It is possible to provide a method for manufacturing a metal wiring of a semiconductor device that can prevent the life of the device, the operation speed and the occurrence of defects.

Features of the semiconductor device manufacturing method according to the present invention for achieving the above object,

Forming an interlayer insulating film on the semiconductor substrate having a predetermined lower structure;

Forming a metal layer on the interlayer insulating film;

Forming a photoresist pattern on the metal layer;

Forming a metal wiring by photo-etching the metal layer exposing the photoresist pattern as a mask;

Firstly treating the surface of the structure with an H 2 O plasma;

Removing the photoresist pattern;

And a step of secondary treatment of the metallization with H2O plasma.

In another aspect of the present invention, the metal layer etching to the secondary H 2 O plasma treatment is carried out in a vacuum state, the primary H 2 O plasma treatment process is carried out under conditions such that Cl ions are removed and the entire photoresist pattern is not removed. The temperature is 200 to 300 ° C., the power is 700 to 1500 W, the pressure is 1000 to 3000 mTorr, and the H 2 O flow rate is 500 to 1000 sccm for 10 to 60 seconds.

In still another aspect of the present invention, the photoresist pattern removing process is removed by O 2 / N 2 plasma, 1000 to 3000mTorr pressure, at a temperature of about 200 to 300 ℃, O2 at a power of 700 to 1500W, 1000 to 5000sccm, N2 Is performed at a flow rate of 200 to 1000 sccm for 100 to 300 seconds, and the secondary H 2 O plasma treatment process is performed under the condition that Cl ions can be removed and the metal wiring is not damaged, and the secondary H 2 O plasma treatment process has a temperature of 200 To 300 ° C, pressure is 1000 to 3000mTorr, H2O flow rate is 500 to 1000sccm, 1 to 60 seconds, characterized in that carried out at 200 to 700W power.

Hereinafter, a metal wire manufacturing method of a semiconductor device according to the present invention will be described in detail with reference to the accompanying drawings.

2A through 2D are diagrams illustrating a process of manufacturing metal wirings of a semiconductor device according to the present invention.

First, although not shown, predetermined lower structures such as an isolation layer and a word line and a bit line are sequentially formed on a semiconductor substrate.

Then, the interlayer insulating film 30 is applied to the entire surface of the structure, and the upper portion of the interlayer insulating film 30 is etched and planarized by a method such as CMP, and then the barrier metal layer 32 and the barrier metal layer 32 are formed on the interlayer insulating film 30. The metal layer 34 made of Al and the photoresist pattern 36 as a metal wiring mask are sequentially formed.

Subsequently, the metal layer 34 and the barrier metal layer 32 exposing the photoresist pattern 36 as a mask are sequentially etched to form metal wires having a pattern of the metal layer 34 and the barrier metal layer 32. The process is etched using Cl gas, BCl 3 gas for sidewall protection, or CHF 3 or N 2 gas, which is a polymer gas. At this time, a large amount of Cl ions 18, which is a major cause of metal corrosion, remains on the surface of the structure. (See FIG. 2A).

Subsequently, the substrate of the structure was moved in a vacuum state, and the first treatment was performed with H 2 O plasma of high temperature / high power to generate O and H radicals. In order to prevent corrosion, the photoresist pattern 36 may also be removed. Here too, some Cl ions 38 remain. The primary H 2 O plasma treatment conditions are such that Cl ions 38 can be removed and the entire photoresist pattern 36 is not removed. The temperature is 200 to 300 ° C., the power is 700 to 1500 W, the pressure is 1000 to 3000 mTorr, The H 2 O flow rate is performed for 10 to 60 seconds at about 500 to 1000 sccm. (See FIG. 2B).

Thereafter, the photoresist pattern 36 is removed by a high temperature O 2 / N 2 plasma to complete the metal wiring including the metal layer 14 pattern and the barrier metal layer 12 pattern. Cl ions 38 remain. In this case, the O2 / N2 plasma treatment process is performed at a pressure of 1000 to 3000 mTorr, at a temperature of about 200 to 300 ° C., at a power of about 700 to 1500 W, at a flow rate of about 1000 to 5000 sccm, and at about 200 to 1000 sccm for N2. To 300 seconds. (See FIG. 2C).

The wafer surface of the structure was then subjected to secondary treatment with H2O plasma of high temperature / low power to completely remove the fine Cl ions 38 residue on the wafer without damaging the metallization, and then cleaning the wafer with solvent and in the air. Expose Here, since Cl ions which cause corrosion of the metal wiring are completely removed, corrosion of the metal wiring does not occur even if exposed to the air for a long time. In addition, the secondary H 2 O plasma treatment condition is a condition that can remove the Cl ions 38, the metal wiring is not damaged, the temperature is 200 to 300 ℃, the pressure is 1000 to 3000mTorr, H2O flow rate is about 500 to 1000sccm It is carried out under conditions of about 1 to 60 seconds, about 200 to 700 W, which is relatively lower than the primary H 2 O plasma treatment. (See FIG. 2D).

The barrier metal layer may not be formed in the above, and a hard mask layer pattern may be provided on the metal layer.

As described above, in the method of manufacturing the metal wiring of the semiconductor device according to the present invention, the metal wiring is patterned using the photoresist pattern as a mask, and H2O plasma treatment is performed before and after the photoresist pattern is removed to remove Cl ions remaining on the wafer. Since solvent cleaning is performed and exposed to the air, corrosion can be prevented even when metal wiring is exposed to moisture in the air for a long time to wait for the next process, thereby preventing the life of the device, operation speed and defects. There is an advantage to improve the yield and reliability of device operation.

Claims (8)

Forming an interlayer insulating film on the semiconductor substrate having a predetermined lower structure; Forming a metal layer on the interlayer insulating film; Forming a photoresist pattern on the metal layer; Forming a metal wiring by photo-etching the metal layer exposing the photoresist pattern as a mask; Firstly treating the surface of the structure with an H 2 O plasma; Removing the photoresist pattern; A method for manufacturing metal wiring in a semiconductor device, comprising the step of secondary processing the metal wiring with H 2 O plasma. The method of claim 1, wherein the metal layer etching to the secondary H 2 O plasma treatment is performed in a vacuum state. The method of claim 1, wherein the first H 2 O plasma treatment process is performed under conditions such that Cl ions are removed and the entire photoresist pattern is not removed. The method of claim 1, wherein the primary H2O plasma treatment process is performed at a temperature of 200 to 300 ° C., a power of 700 to 1500 W, a pressure of 1000 to 3000 mTorr, and a H 2 O flow rate of 500 to 1000 sccm for 10 to 60 seconds. Method for manufacturing metal wiring of semiconductor device. The method of claim 1, wherein the photoresist pattern removing process is performed by removing O 2 / N 2 plasma, at a pressure of 1000 to 3000 mTorr, at a temperature of about 200 to 300 ° C., at a temperature of 700 to 1500 W, at 1000 to 5000 sccm, and at 200 to 200 N. A metal wiring manufacturing method for a semiconductor device, characterized in that performed for 100 to 300 seconds at a flow rate of 1000sccm. The method of claim 1, wherein the secondary H 2 O plasma treatment process is performed under conditions in which Cl ions can be removed and the metal wiring is not damaged. The method of claim 1, wherein the secondary H2O plasma treatment process is carried out at a temperature of 200 to 300 ℃, pressure of 1000 to 3000mTorr, H2O flow rate of 500 to 1000sccm, about 1 to 60 seconds, 200 to 700W power. Method for manufacturing metal wiring of semiconductor device. The method of manufacturing a semiconductor device according to claim 1, further comprising a hard mask layer pattern on the metal layer.

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