JPH0955357A - Semiconductor manufacturing apparatus and thin film deposition method - Google Patents

Abstract

(57) [Summary] [Object] To provide a semiconductor manufacturing apparatus capable of efficiently depositing plural kinds of thin films on a semiconductor substrate. A semiconductor manufacturing apparatus for depositing a thin film on a semiconductor substrate 1 with target atoms knocked out by gas molecules ionized by discharge under reduced pressure, and a semiconductor is provided in a chamber 4 into which a processing gas 8 is introduced. A stage 5 that holds the substrate 1 is installed. Each support surface 12a, 12
The target electrode 12 is provided so that each of b can face the semiconductor substrate 1. Target electrode 12
Targets Mo17 and Al18, which are different from each other, are attached to the support surfaces 12a and 12b, respectively. The target electrode 12 is provided in parallel with the semiconductor substrate 1 and attached to a shaft 14 rotated by a motor 13.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a semiconductor manufacturing apparatus and a thin film deposition method, and more particularly to a technique effectively applied to thin film deposition by sputtering.

[0002]

2. Description of the Related Art Circuit elements formed on a semiconductor substrate are
As you can see from the cross-sectional structure, thin films are made up of multiple layers. These thin films may be semiconductors, insulators, or conductors. As a thin film forming technique for such a semiconductor substrate, CVD (Chemical Vapor Deposition) which is a chemical technique and PVD (Physical Vapor Deposition) which is a physical technique are known. As a typical PVD, there is tapping of target atoms by ions, that is, sputtering, and a sputtering apparatus is a semiconductor manufacturing apparatus for depositing a thin film on a semiconductor substrate by sputtering.

For example, as described in "Introduction to Ultrafine Machining" (published on June 20, 1989), P120-P124, published by Ohmsha, Inc., a sputtering apparatus is attached to a target electrode which is a cathode. The target material atoms (hereinafter referred to as “target atoms”) are repelled by the ionized gas molecules and deposited as a thin film on the semiconductor substrate provided on the anode. Here, published by the Industrial Research Board, “Electronic Material Separate Volume / VLSI Manufacturing, Test Equipment Guidebook”, 1994 edition (issued on November 20, 1993), P41
As described in ~ P47 etc., the sputtering system is equipped with multiple chambers in which different target materials are set, facing a common transfer chamber, and the semiconductor substrate is sequentially introduced into each chamber to provide multiple types of chambers. There has been adopted a multi-chamber system in which thin films are sequentially formed.

[0004]

However, according to this multi-chamber system, for example, MoSi ₂ −
Al-MoSi ₂ (MoSi ₂ : molybdenum silicide,
In the case of forming a three-layer thin film of Al: aluminum), two chambers in which Mo (molybdenum) is installed as a target material and one chamber in which Al is installed require a total of three chambers, There is a problem that the device becomes large.

Further, when the target material is consumed by sputtering and has reached the end of its life, it is necessary to replace it with a new target material. If the chamber is opened to the atmosphere for this work, the downtime becomes very large. Throughput is significantly reduced.

[0006] As a technique for extending the life of the target material and reducing the frequency of replacement work, published by the Industrial Research Committee, "Electronic Material Separate Volume / VLSI Manufacturing, Test Equipment Guidebook", 1993 edition (November 20, 1992) (Issue), P54 proposes an integrated target that does not use solder material, but it seems that it is difficult to extend its life overwhelmingly.

Therefore, an object of the present invention is to provide a technique capable of efficiently depositing plural kinds of thin films on a semiconductor substrate while miniaturizing the device.

Another object of the present invention is to provide a technique capable of reducing the frequency of replacement work of a target material.

The above and other objects and novel features of the present invention will become apparent from the description of the present specification and the accompanying drawings.

[0010]

SUMMARY OF THE INVENTION Among the inventions disclosed in the present application, typical ones will be outlined as follows.

That is, the semiconductor manufacturing apparatus according to the present invention is an apparatus for depositing a thin film on a semiconductor substrate with target atoms knocked out by gas molecules ionized by discharge under reduced pressure, and a chamber into which a processing gas is introduced. A stage for holding the semiconductor substrate is installed therein. The target electrode is provided so that each supporting surface can face the semiconductor substrate. First and second target materials are attached to the respective support surfaces of the target electrode. In this device, the target electrode may be provided in parallel with the semiconductor substrate and attached to the shaft rotated by the rotation driving means.

Different target materials such as molybdenum and aluminum can be attached to the first and second target materials. Also, the same target material can be attached.

The thin film deposition method according to the present invention is a method for depositing a thin film on a semiconductor substrate with target atoms knocked out by gas molecules ionized by discharge under reduced pressure, and is used for depositing on each support surface of a target electrode. Different target materials are attached to each other, one of these two target materials is set at a position facing the semiconductor substrate to deposit a thin film, and then the other target material is opposed to the semiconductor substrate. It is set to the position to deposit different kinds of thin films.

The thin film deposition method according to the present invention is a method of depositing a thin film on a semiconductor substrate with target atoms knocked out by ionized gas molecules by discharge under reduced pressure, and supports each target electrode. The same target material is attached to the surface, and one of these two target materials is set at a position facing the semiconductor substrate to deposit a thin film, and when the target material reaches the end of its life, another One target material is set at a position facing the semiconductor substrate to deposit a thin film.

[0015]

According to the above-mentioned means, since each supporting surface of the target electrode can be opposed to the semiconductor substrate and different target materials are attached to each other, a plurality of types of thin films can be efficiently formed in one chamber. Will be possible. And
As a result, the number of chambers can be reduced and the device can be downsized.

Since the same target material is attached so that each support surface of the target electrode can face the semiconductor substrate, the total life of the two target materials becomes the target material replacement timing, and the frequency of the replacement work is about the same. It can be reduced to half.

[0017]

Embodiments of the present invention will now be described in detail with reference to the drawings.

(Embodiment 1) FIG. 1 is a sectional view showing a semiconductor manufacturing apparatus which is an embodiment of the present invention, and FIGS.
FIG. 6 is an explanatory view showing a mechanism of thin film deposition on a semiconductor substrate by the semiconductor manufacturing apparatus of FIG.

As shown in FIG. 1, the semiconductor manufacturing apparatus according to this embodiment has an ionized gas molecule P ₁ (FIGS. 2 and 3).
Target atoms P ₂ and P ₃ sputtered on the substrate (FIG. 2,
3) is a sputtering apparatus for depositing a thin film on a semiconductor substrate 1, and a vacuum pump 2 such as a diffusion pump for evacuating the inside to a predetermined vacuum degree is provided in a chamber 4 connected through a vacuum pipe 3. A stage 5 for holding the semiconductor substrate 1 is installed. This stage 5 as an anode is attached to the chamber 4 via an insulating material 6 and is set to the ground potential. The support portion 5 a of the stage 5 is led out of the chamber 4 and is connected to a water supply pump that supplies the cooling water 7 to the flow path formed in the stage 5.

A gas supply pipe 9 for introducing a processing gas 8 such as an inert gas such as Ar (argon) or Xe (xenon) is connected to the chamber 4.
Further, valves 10 and 11 are attached to the vacuum pipe 3 and the gas supply pipe 9, respectively, so that these paths can be opened and closed.

A disk-shaped target electrode 12 serving as a cathode is provided at a position facing the stage 5. The target electrode 12 is provided in parallel with the semiconductor substrate 1 and is attached to a shaft 14 which is rotated by a motor (rotational driving means) 13, and each of the support surfaces 12 is provided.
Both a and 12b can face the semiconductor substrate 1. Instead of rotating the target electrode 12 in this way, for example, the target electrode 12 may be moved along an endless track to change the directions of the support surfaces 12a and 12b.

Chamber 4 via insulating materials 15a and 15b
The target electrode 1 is attached to the shaft 14 attached to the
A DC power supply 16 for applying a DC negative voltage is connected to the terminal 2. Therefore, when a voltage is applied to the target electrode 12, glow discharge is generated between the stage 5 that is the anode and the target electrode 12 that is the cathode. Note that, for example, 13.56M is applied to the target electrode 12.
A high frequency voltage such as Hz may be applied.

The shaft 14 on the side not connected to the motor 13 is led to the outside of the chamber 4 and supplies the cooling water 7 to the flow passage formed in the target electrode 12 like the stage 5 described above. It is connected to a feed pump.

One support surface 12a of the target electrode 12
Mo (first target material) 17 is attached to the other side, and Al (second target material) 18 is attached to the other supporting surface 12b. And these target materials 1
Reference numerals 7 and 18 denote target electrodes 12 rotated by a motor.
Either of them is set to a position facing the semiconductor substrate 1.

The thin film deposition on the semiconductor substrate 1 by the semiconductor manufacturing apparatus of this embodiment is performed as follows.

First, as shown in FIG. 2, a target material Mo17 attached to one supporting surface 12a of the target electrode 12 is set so as to face the semiconductor substrate 1. Then, the inside of the chamber 4 is evacuated to introduce the processing gas 8 and the DC power source 16 supplies electric power of, for example, about 1 kW to the target electrode 12 to generate glow discharge and ionize the gas molecule P ₁ to generate Mo. MoS as barrier metal by sputtering target atom P ₂
A thin film of i ₂ is formed on the semiconductor substrate 1. The sputtering with Mo17 is performed for about 30 seconds, for example.

Next, as shown in FIG. 3, the target electrode 12 is rotated to set the target material Al18 attached to the other support surface 12b at an opposing position, and for example, a power of about 9 to 12 kW is applied. A target atom P ₃ of Al is sputtered below to form an Al thin film as a wiring layer. This sputtering is performed for about 1 min, for example.

After depositing a thin film of Al, the target electrode 12 is rotated, Mo17 is set again at a position facing the semiconductor substrate 1 as shown in FIG. 2, and sputtering is performed under the same conditions as described above. A MoSi ₂ thin film as a cap is formed on the wiring layer.

As described above, in the semiconductor manufacturing apparatus of this embodiment, the respective support surfaces 12a, 12 of the target electrode 12 are formed.
b so that it can face the semiconductor substrate 1 and Mo17 and Al18
Since different target materials are attached to each other, it is possible to efficiently form a plurality of types of thin films (here, two types and three layers of thin films) by an apparatus having one chamber 4.

A thin film that does not require etching is deposited,
When a thin film is further deposited on the upper layer, the target electrode 12 can be rotated to continuously deposit different thin films, which eliminates the need to transfer the semiconductor substrate 1 from one chamber to another chamber. The time can be shortened.

(Embodiment 2) FIGS. 4 and 5 are explanatory views showing the mechanism of thin film deposition on a semiconductor substrate by a semiconductor manufacturing apparatus according to another embodiment of the present invention.

As shown in the figure, the semiconductor manufacturing apparatus according to the present embodiment has both supporting surfaces 12a, 12 of the target electrode 12.
In b, for example, Mo (first target material) 17a, Mo
The same target material as (second target material) 17b is attached, and the other device configurations are the same as those of the semiconductor manufacturing apparatus of the first embodiment. In this embodiment, the two Mo 17a and 17b have the same size and weight, but they may have different sizes.

Thin film deposition in the semiconductor manufacturing apparatus of this embodiment is carried out as follows.

First, as shown in FIG. 4, the Mo 17a attached to one supporting surface 12a of the target electrode 12 is used.
Are set so as to face the semiconductor substrate 1, and sputtering is performed. Thus, using Mo17a as a target material, thin films are sequentially formed on the plurality of semiconductor substrates 1. The sputtered Mo17a reaches the end of its life at, for example, 400 kWh.

When the Mo17a has reached the end of its life, as shown in FIG. 4, the target electrode 12 is rotated to set the Mo17b attached to the other supporting surface 12b at the position opposite to the semiconductor substrate 1, and similarly. Multiple semiconductor substrates 1
A thin film is deposited on. As mentioned above, Mo17b is M
Since it has the same size and weight as o17a, this Mo17b also reaches the end of its life at 400kWh.

After both the Mo 17a and 17b have reached the end of their lives, the chamber 4 (FIG. 1) is opened to the atmosphere and the target material is replaced.

As described above, according to the semiconductor manufacturing apparatus of this embodiment, since the same target materials Mo17a and 17b are attached to the respective supporting surfaces 12a and 12b of the rotatable target electrode 12, One Mo
Even if 17a reaches the end of its life, the other Mo17b can be used as a target material to continue the construction work.
The total life of 800kWh by 7b becomes the target material replacement timing, and the frequency of replacement work can be reduced to half.

Although the invention made by the present inventor has been specifically described based on the embodiments, the present invention is not limited to the embodiments and various modifications can be made without departing from the scope of the invention. Needless to say.

For example, although Mo17, 17a, 17b and Al18 are used as the target material in this embodiment, the target material is not limited to these and various other targets such as Ti (titanium) and W (tungsten) are used. Materials can be used.

In the above description, the case where the invention made by the present inventor is mainly applied to the manufacture of semiconductors, which is the field of application of the background, has been described, but the present invention is not limited to this. It can be applied to various fields of thin film formation.

[0041]

The effects obtained by the typical inventions among the inventions disclosed in the present application will be briefly described as follows.

(1) That is, according to the thin film deposition technique of the present invention, since each support surface of the target electrode can face the semiconductor substrate and different target materials are attached to each other, a plurality of target materials can be attached to one chamber. It becomes possible to efficiently form a thin film of a seed.

(2) As a result, the number of chambers can be reduced and the apparatus can be downsized.

(3) When depositing a thin film that does not require etching and further depositing a thin film on top of it, different thin films can be deposited successively, so that the thin film deposition time can be shortened. It becomes possible to plan.

(4) Further, according to the thin film deposition technique of the present invention, since the same target material is attached so that each supporting surface of the target electrode can face the semiconductor substrate, the total life of the two target materials is Is the target material replacement timing, and the frequency of replacement work can be reduced to about half.

(5) As a result, the operating time of the device is increased and the throughput can be improved.

[Brief description of drawings]

FIG. 1 is a sectional view showing a semiconductor manufacturing apparatus according to an embodiment of the present invention.

FIG. 2 is an explanatory view showing a mechanism of thin film deposition on a semiconductor substrate by the semiconductor manufacturing apparatus of FIG.

3 is an explanatory view showing a mechanism of thin film deposition on a semiconductor substrate by the semiconductor manufacturing apparatus of FIG.

FIG. 4 is an explanatory view showing a mechanism of thin film deposition on a semiconductor substrate by a semiconductor manufacturing apparatus according to another embodiment of the present invention.

FIG. 5 is an explanatory view showing a mechanism of thin film deposition on a semiconductor substrate by a semiconductor manufacturing apparatus according to another embodiment of the present invention.

[Explanation of symbols]

1 Semiconductor Substrate 2 Vacuum Pump 3 Vacuum Piping 4 Chamber 5 Stage 5a Supporting Part 6 Insulating Material 7 Cooling Water 8 Processing Gas 9 Gas Supply Pipe 10 Valve 11 Valve 12 Target Electrode 12a Supporting Surface 12b Supporting Surface 13 Motor (Rotating Driving Means) 14 Shaft 15a Insulation material 15b Insulation material 16 DC power supply 17 Mo (first target material) 17a Mo (first target material) 17b Mo (second target material) 18 Al (second target material) P ₁ gas molecule P ₂ target atom P ₃ target atom

Claims (7)

[Claims] 1. A semiconductor manufacturing apparatus for depositing a thin film on a semiconductor substrate with target atoms knocked out by gas molecules ionized by discharge under reduced pressure, which is installed in a chamber into which a processing gas is introduced. A target electrode to which a stage for holding the semiconductor substrate and a supporting surface of the stage are provided so that each supporting surface can face the semiconductor substrate, and a predetermined voltage is applied; A semiconductor manufacturing apparatus having the first and second target materials formed. 2. The semiconductor manufacturing apparatus according to claim 1, wherein the target electrode is provided in parallel with the semiconductor substrate and is attached to a shaft rotated by a rotation driving means. 3. The semiconductor manufacturing apparatus according to claim 1, wherein the first target material and the second target material are target materials different from each other. 4. The semiconductor manufacturing apparatus according to claim 3, wherein the first target material is molybdenum and the second target material is molybdenum.
The semiconductor manufacturing apparatus is characterized in that the target material is aluminum. 5. The semiconductor manufacturing apparatus according to claim 1, wherein the first and second target materials are the same target material. 6. A thin film deposition method for depositing a thin film on a semiconductor substrate with target atoms knocked out by gas molecules ionized by discharge under reduced pressure, which are different from each other on respective supporting surfaces of target electrodes. A target material is attached, one of the two target materials is set at a position facing the semiconductor substrate, and a thin film is deposited on the semiconductor substrate, and then the other target material. Is set at a position facing the semiconductor substrate, and a thin film of a type different from the thin film is deposited on the semiconductor substrate. 7. A thin film deposition method for depositing a thin film on a semiconductor substrate with target atoms knocked out by gas molecules ionized by discharge under reduced pressure, wherein the same target is provided on each support surface of a target electrode. A target material is attached, one of the two target materials is set at a position facing the semiconductor substrate, and a thin film is deposited on the semiconductor substrate. Then, the other target material is set at a position facing the semiconductor substrate and the thin film is deposited on the semiconductor substrate.