TWI543262B - Method for manufacturing barrier layer, semiconductor device and method for manufacturing the same - Google Patents

Description

Method for manufacturing barrier layer, semiconductor element and method of manufacturing same

The present invention relates to a semiconductor device fabrication technique, and more particularly to a method of fabricating a barrier layer.

Large size, high update frequency, high resolution, touch operation and narrow bezel are the current trends in flat panel displays and touch panels. Copper's conductivity and electrical resistance are superior to aluminum, so the use of copper in flat-panel displays and touch panels has become an important development trend. However, copper is easily diffused in the tantalum film, resulting in poor manufacturing quality. Therefore, a barrier layer is generally provided between the copper and tantalum films. In addition to the function of preventing copper from diffusing into the germanium film, the barrier layer must also have good adhesion to the copper film to improve the stability of the product.

There are several solutions to the current problems. U.S. Patent No. 6,271,131 discloses a method of forming a ruthenium-containing barrier layer by chemical vapor deposition (CVD) using a tantalum or iridium platinum alloy as a diffusion barrier layer. However, rhodium and platinum are precious metals, which are expensive and insufficiently produced to meet the mass production needs of flat panel displays.

U.S. Patent Publication No. 20050070097 proposes a A multilayer diffusion barrier layer of a semiconductor element and a method of manufacturing the same, which are used as a barrier layer by using a multilayer film having a thickness of only a few atomic thickness. However, in order to form a multilayer film having a very small thickness, a very precise manufacturing process is required to achieve a barrier effect, and it is not a general production facility that can produce such a film.

The Republic of China Patent Publication No. I198198 proposes a method for producing a plasma-nitrided titanium-based barrier layer, which discloses a precursor such as titanium chloride or hydrogen, which is deposited by a chemical vapor deposition process and then nitrided. The surface treatment of the slurry forms a barrier layer. The chemical vapor deposition process used in this patent has an operating temperature of 490 °C. Since this temperature has exceeded the softening temperature of the glass substrate used in the flat panel display and the touch panel, the method cannot be applied to the copper process of the flat panel display and the touch panel.

SUMMARY OF THE INVENTION Accordingly, it is an object of the present invention to provide a method for fabricating a barrier layer, a semiconductor device, and a method for fabricating the same, which utilize a bismuth aluminum target for a physical vapor deposition process and use nitrogen as a process gas for the semiconductor device. A tantalum aluminum nitride is formed on the thin film layer as a barrier layer. The bismuth aluminum nitride barrier layer can effectively prevent copper from diffusing into the ruthenium film and maintain the quality of the copper film. In addition, the use of niobium and aluminum as target materials is relatively low in production cost, which can reduce production costs.

Another object of the present invention is to provide a method for fabricating a barrier layer and a semiconductor device and a method for fabricating the same, which use a general physical vapor deposition process for depositing a barrier layer, and thus can be produced by using an existing deposition apparatus. A barrier layer of quality conforming to the standard. Moreover, the invention is used The physical vapor deposition process is a low-temperature process, and when the semiconductor component used in the liquid crystal display panel is fabricated, the softening of the substrate is not caused, and the product yield can be improved.

According to the above object of the present invention, a method of manufacturing a barrier layer is proposed. The manufacturing method of the barrier layer includes the following steps. A substrate is provided in which a tantalum film is formed on the substrate. The physical vapor deposition process is performed by using a tantalum aluminum target to form a barrier layer covering the tantalum film, wherein the tantalum aluminum target is composed of aluminum and tantalum, and the process gas of the physical vapor deposition process contains nitrogen.

According to an embodiment of the invention, the above-described tantalum aluminum target comprises 15% by weight to 75% by weight of aluminum.

According to another embodiment of the present invention, the barrier layer is a composite layer, and the barrier layer comprises tantalum nitride and aluminum nitride.

According to still another embodiment of the present invention, the physical vapor deposition process comprises a direct current vacuum magnetron sputtering method, a radio frequency vacuum magnetron sputtering method or a reactive sputtering method.

According to still another embodiment of the present invention, the tantalum film is a polycrystalline germanium film or an amorphous germanium film.

According to the above object of the present invention, a method of manufacturing a semiconductor device is further proposed. The method of manufacturing a semiconductor device includes the following steps. A substrate is provided. The first physical vapor deposition process is performed using the tantalum target to form a tantalum film covering the substrate. The second physical vapor deposition process is performed by using a tantalum aluminum target to form a barrier layer covering the tantalum film, wherein the tantalum aluminum target is composed of aluminum and tantalum, and the process gas of the second physical vapor deposition process comprises nitrogen gas. . Performing a third physical vapor deposition process using a copper target to form a thin copper The film is covered on the barrier layer.

According to an embodiment of the invention, the above-described tantalum aluminum target comprises 15% by weight to 75% by weight of aluminum.

According to another embodiment of the present invention, the barrier layer is a composite layer, and the barrier layer comprises tantalum nitride and aluminum nitride.

According to still another embodiment of the present invention, the second physical vapor deposition process comprises a direct current vacuum magnetron sputtering method, a radio frequency vacuum magnetron sputtering method or a reactive sputtering method.

According to still another embodiment of the present invention, the first physical vapor deposition process and the third physical vapor deposition process include a direct current vacuum magnetron sputtering method or a radio frequency vacuum magnetron sputtering method.

According to still another embodiment of the present invention, the ruthenium film layer is a polycrystalline germanium film or an amorphous germanium film.

According to the above object of the present invention, a semiconductor element is further proposed. The semiconductor element includes a substrate, a tantalum film, a barrier layer, and a copper film. The tantalum film is placed on the substrate. The barrier layer is disposed on the germanium film, wherein the barrier layer is a composite layer, and the barrier layer comprises tantalum nitride and aluminum nitride. A copper film is disposed on the barrier layer.

According to an embodiment of the invention, the ruthenium film layer is a polycrystalline germanium film or an amorphous germanium film.

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201‧‧‧Substrate

203‧‧‧矽film

205‧‧‧Barrier layer

207‧‧‧ copper film

The above and other objects, features, advantages and embodiments of the present invention will become more apparent and understood.

1 is a flow chart showing a method of fabricating a semiconductor device in accordance with an embodiment of the present invention.

2A and 2D are cross-sectional views showing processes of various steps of a method of fabricating a semiconductor device in accordance with an embodiment of the present invention.

Please refer to FIG. 1 and FIG. 2A to FIG. 2D simultaneously. FIG. 1 is a flow chart showing a method of manufacturing a semiconductor device according to an embodiment of the present invention, and FIG. 2A and FIG. 2D are diagrams. A process cross-sectional view of each step of a method of fabricating a semiconductor device in accordance with an embodiment of the present invention. In the present embodiment, when the method 100 for manufacturing a semiconductor device shown in FIG. 1 is performed, the substrate 201 as shown in FIG. 2A can be provided as described in step 102. In some embodiments, the substrate 201 can be, for example, a germanium wafer, a glass substrate, or a plastic substrate.

Next, as described in step 104 of FIG. 1, the first physical vapor deposition process is performed using the germanium target, whereby the germanium film 203 is formed to cover the surface of the substrate 201. In some embodiments, the first physical vapor deposition process can be performed using a direct current vacuum magnetron sputtering method or a radio frequency vacuum magnetron sputtering method. Moreover, as shown in FIG. 2B, the tantalum film 203 may be a polycrystalline germanium film or an amorphous germanium film in response to different applications of the semiconductor device. For example, when a semiconductor element is applied to a liquid crystal display, the germanium film 203 may be an amorphous germanium film.

After the germanium film 203 is formed on the surface of the substrate 201, a second physical vapor deposition process may be performed using the tantalum aluminum target as described in step 106 to form a barrier layer 205 overlying the germanium film 203. Figure 2C shows. In this embodiment, the tantalum aluminum target is composed of aluminum and tantalum. In some embodiments, the hafnium aluminum target comprises an aluminum content of from 15 wt% to 75 wt%, with the balance being the content of niobium. Moreover, the process gas used in the second physical vapor deposition process of this example contains nitrogen gas. Therefore, in some embodiments, the barrier layer 205 is a composite layer comprising tantalum nitride and aluminum nitride. In some embodiments, the second physical vapor deposition process can be performed using a direct current vacuum magnetron sputtering method, a radio frequency vacuum magnetron sputtering method, or a reactive sputtering method.

Continuing to refer to FIG. 1 and FIG. 2D, after the barrier layer 205 is overlaid on the ruthenium film 203, a third physical vapor deposition process may be performed using a copper target as described in step 108 to form a copper film 207. Covered on the barrier layer 205. In some embodiments, the third physical vapor deposition process can be performed using a direct current vacuum magnetron sputtering method or a radio frequency vacuum magnetron sputtering method.

Hereinafter, the effects of the semiconductor element produced by the method for producing a semiconductor device of the present invention will be described using Comparative Example 1, Comparative Example 2, and Example 1-3, but it is not intended to limit the present invention. Those skilled in the art can make various changes and modifications without departing from the spirit and scope of the invention.

When manufacturing the semiconductor device of Comparative Example 1, a glass substrate was first provided, and after the glass substrate was washed with deionized water, the residual water droplets on the surface of the glass substrate were blown dry with nitrogen, and then the glass substrate was placed in an oven at 120 ° C. Dry at temperature. Next, a deposition process is performed using a germanium target to form a germanium film over the glass substrate. Subsequently, a deposition process was performed using a copper target to form a copper film on the tantalum film, and the semiconductor device of Comparative Example 1 was completed. Production. The completed semiconductor device of Comparative Example 1 was placed in an oven and baked at a temperature of 350 ° C for 1 hour, and then taken out and cooled at room temperature. It can be seen from the baked semiconductor component that the copper film has diffused into the tantalum film.

Further, in the manufacture of the semiconductor element of Comparative Example 2, a glass substrate was first provided, and after the glass substrate was washed with deionized water, the residual water droplets on the surface of the glass substrate were blown dry with nitrogen, and then the glass substrate was placed in an oven at 120 Dry at °C. Next, a deposition process is performed using a germanium target to form a germanium film over the glass substrate. Subsequently, a reactive sputtering process was performed using a 75 wt% 矽-25 wt% aluminum target, and the process gas was oxygen to form a ruthenium aluminum oxide film on the ruthenium film. Then, a deposition process was performed using a copper target to form a copper film on the tantalum aluminum oxide film, and the fabrication of the semiconductor device of Comparative Example 2 was completed. The completed semiconductor device of Comparative Example 2 was placed in an oven and baked at a temperature of 350 ° C for 1 hour, and then taken out and cooled at room temperature. It can be seen from the baked semiconductor component that the copper film has diffused into the tantalum film. This means that the yttrium aluminum oxide film does not effectively block the diffusion of copper in the ruthenium film.

On the other hand, in the manufacture of the semiconductor element of Example 1, a glass substrate was first provided, and after the glass substrate was washed with deionized water, the residual water droplets on the surface of the glass substrate were blown dry with nitrogen, and then the glass substrate was placed in an oven. Dry at a temperature of 120 °C. Next, a physical vapor deposition process is performed using a germanium target to form a germanium film over the glass substrate. Subsequently, a reactive sputtering process was performed using 85 wt% 矽-15 wt% aluminum target and using nitrogen as a process gas to form a yttrium aluminum nitride film on the ruthenium film. Then, a physical vapor deposition process was performed using a copper target to form a copper film on the tantalum aluminum nitride film, and the fabrication of the semiconductor device of Example 1 was completed. will The completed semiconductor device of Example 1 was placed in an oven and baked at a temperature of 350 ° C for 1 hour, and then taken out and cooled at room temperature. It is known from the baked semiconductor element that the copper film maintains its original form and color. That is to say, the copper film is not diffused into the ruthenium film, so that the quality of the ruthenium film and the copper film can be ensured. It can be seen that the tantalum aluminum nitride film formed between the copper film and the tantalum film has the effect of blocking the diffusion of copper to the tantalum film.

In addition, in Example 2, a reactive sputtering process was also performed using a bismuth aluminum target, and nitrogen gas was introduced as a process gas in the reactive sputtering process. In the manufacture of the semiconductor device of Example 2, the glass substrate was also provided first, and after the glass substrate was washed with deionized water, the residual water droplets on the surface of the glass substrate were blown dry with nitrogen, and then the glass substrate was placed in an oven at 120 ° C. The temperature is dried. Next, a physical vapor deposition process is performed using a germanium target to form a germanium film over the glass substrate. Subsequently, a reactive sputtering process was performed with a 50 wt% 矽-50 wt% aluminum target and nitrogen gas as a process gas to form a yttrium aluminum nitride film on the ruthenium film. Then, a physical vapor deposition process was performed using a copper target to form a copper film on the tantalum aluminum nitride film, and the fabrication of the semiconductor device of Example 2 was completed. The completed semiconductor device of Example 2 was placed in an oven and baked at a temperature of 350 ° C for 1 hour, and then taken out and cooled at room temperature. It can be seen from the semiconductor element after baking that the copper film maintains its original shape and color, meaning that the copper film does not diffuse into the ruthenium film, thereby ensuring the quality of the ruthenium film and the copper film. Further, as a result of performing the Baige adhesion test on the semiconductor element of Example 2, it was found that the adhesion between the copper film and the yttrium aluminum nitride film was good, and the optimum 5B level as specified in ASTM D3359 was achieved. This means that the yttrium aluminum nitride film not only blocks copper. The film is diffused to the tantalum film and has good adhesion to the copper film, thereby improving the product quality of the semiconductor element.

Similarly, in Example 3, a reactive sputtering process was also performed using a bismuth aluminum target, and nitrogen gas was introduced as a process gas in the reactive sputtering process. In the manufacture of the semiconductor device of Example 3, a glass substrate was also provided first, and the glass substrate was washed with deionized water, and then the residual water droplets on the surface of the glass substrate were blown dry with nitrogen, and then the glass substrate was placed in an oven at 120 ° C. The temperature is dried. Next, a physical vapor deposition process is performed using a germanium target to form a germanium film over the glass substrate. Subsequently, a reactive sputtering process was performed with a 75 wt% 矽-25 wt% aluminum target using nitrogen as a process gas to form a yttrium aluminum nitride film on the ruthenium film. Then, a physical vapor deposition process was performed using a copper target to form a copper film on the tantalum aluminum nitride film, and the fabrication of the semiconductor device of Example 3 was completed. The completed semiconductor device of Example 3 was placed in an oven and baked at a temperature of 350 ° C for 1 hour, and then taken out and cooled at room temperature. It can be seen from the baked semiconductor element that the copper film maintains its original shape and color, meaning that the copper film does not diffuse into the ruthenium film, and the quality of the ruthenium film and the copper film can be ensured.

It can be seen from the above embodiments that the present invention utilizes a bismuth aluminum target for a physical vapor deposition process and uses nitrogen as a process gas to form yttrium aluminum nitride on the ruthenium film layer of the semiconductor device as a barrier layer. The bismuth aluminum nitride barrier layer can effectively block the diffusion of copper into the ruthenium film and maintain the quality of the original copper film. In addition, the use of niobium and aluminum as target materials is relatively low in production cost, which can reduce production costs.

It can be seen from the above embodiments that the present invention can use general physical gas. The phase deposition process is used to deposit the barrier layer, so that the existing deposition equipment can be used to produce a quality-compliant barrier layer. Moreover, the physical vapor deposition process used in the present invention is a low-temperature process, and when the semiconductor device used in the liquid crystal display panel is fabricated, the substrate is not softened, and the product yield can be improved.

Although the present invention has been disclosed in the above embodiments, it is not intended to limit the present invention, and the present invention can be modified and modified without departing from the spirit and scope of the present invention. The scope is subject to the definition of the scope of the patent application attached.

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Claims (13)

A method for manufacturing a barrier layer, comprising: providing a substrate, wherein a germanium film is formed on the substrate; and performing a physical vapor deposition process using a germanium aluminum target to form a barrier layer overlying the germanium film Wherein the tantalum aluminum target is composed of aluminum and tantalum, and one of the process gases of the physical vapor deposition process comprises a nitrogen gas. The method for producing a barrier layer according to claim 1, wherein the bismuth aluminum target comprises 15% by weight to 75% by weight of aluminum. The method for fabricating a barrier layer according to claim 1, wherein the barrier layer is a composite layer, and the barrier layer comprises tantalum nitride and aluminum nitride. The method for fabricating a barrier layer according to claim 1, wherein the physical vapor deposition process comprises a direct current vacuum magnetron sputtering method, a radio frequency vacuum magnetron sputtering method or a reactive sputtering method. The method for producing a barrier layer according to claim 1, wherein the germanium film is a polycrystalline germanium film or an amorphous germanium film. A method of manufacturing a semiconductor device, comprising: providing a substrate; performing a first physical vapor deposition process using a germanium target to form a germanium film over the substrate; and performing a second physical use with a germanium aluminum target Vapor deposition process to form a barrier layer covering the tantalum film, wherein the tantalum aluminum target is composed of aluminum and tantalum, and one of the second physical vapor deposition processes comprises a nitrogen gas; and using a copper target A three physical vapor deposition process is performed to form a copper film overlying the barrier layer. The method of manufacturing a semiconductor device according to claim 6, wherein the bismuth aluminum target comprises 15% by weight to 75% by weight of aluminum. The method of fabricating a semiconductor device according to claim 6, wherein the barrier layer is a composite layer, and the barrier layer comprises tantalum nitride and aluminum nitride. The method of fabricating a semiconductor device according to claim 6, wherein the second physical vapor deposition process comprises using a direct current vacuum magnetron sputtering method, a radio frequency vacuum magnetron sputtering method or a reactive sputtering method. . The method of manufacturing a semiconductor device according to claim 6, wherein the first physical vapor deposition process and the third physical vapor deposition process comprise using a direct current vacuum magnetron sputtering method or a radio frequency vacuum magnetron sputtering method. Plating method. The method of manufacturing a semiconductor device according to claim 6, wherein the ruthenium film layer is a polysilicon film or an amorphous germanium film. A semiconductor component comprising: a substrate; a film disposed on the substrate; a barrier layer disposed on the germanium film, wherein the barrier layer is a composite layer, and the barrier layer comprises tantalum nitride and aluminum nitride; A copper film is disposed on the barrier layer. The semiconductor device of claim 12, wherein the germanium film layer is a polysilicon film or an amorphous germanium film.