JPH06207269A - Formation of thin film and sputtering device - Google Patents

Abstract

PURPOSE:To easily form a thin film having a good thickness distribution on a large-sized substrate in the sputtering device used in forming a thin film by enlarging a film forming region having a uniform film thickness distribution. CONSTITUTION:The substrate holder 1 of a sputtering device is made detachable. The holder 1 is not parallel to the target surface, the upper and lower parts of the holder are brought close to a target 9, the center is kept away from the target 9, and the holder 1 is inclined to the target surface at an angle of <=45 deg.. Consequently, the cost is reduced, the thicknesses of the films on plural substrates are uniformized, and hence the throughput is increased.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for forming various thin films, and more particularly to a method for forming a thin film suitable for forming a large area and reducing variations among substrates in a simultaneously formed substrate.

[0002]

2. Description of the Related Art Conventionally, LSI (Large Scale Intergrate)
d)), wiring of thin film circuit boards, sputtering is used to form thin films such as resistors because of its controllability, and in particular, the planar magnetron method, which enables high-speed film formation, has been adopted. These methods include Thin Film Processes, pages 131 to 173 (Thin FilmP
rocesses (1978) pp131-173). In the film formation by the sputtering method, there is often adopted a method in which the substrate is moved in front of the target in order to increase the throughput. Examples thereof are shown in FIGS. 7 to 10.
FIG. 7 is a diagram schematically showing a carousel type (side sputtering) sputtering device, and FIG. 8 is a diagram showing a positional relationship between a target and a substrate in the sputtering device shown in FIG. In the figure, 1 is a substrate holder, 2 is a substrate, 7 is a vacuum chamber, 8 is a sputtering cathode, 9 is a sputtering target, and 10 is a sputtering target.
Is a high frequency power source, 11 is a rotation axis of the substrate holder,
Indicates the rotation direction of the substrate holder. This apparatus is a method of processing a large number of substrates by rotating a substrate holder to which the substrates are attached during sputtering. Further, FIG. 9 is a diagram schematically showing a vertical transfer type sputtering apparatus.
0 is a diagram showing the positional relationship between the target and the substrate in the sputtering apparatus shown in FIG. In the figure, 1
Is a substrate holder, 2 is a substrate, 7 is a vacuum chamber, 8 is a sputtering cathode, 9 is a sputtering target, 10 is a high frequency power source, and 200 is a moving direction of the substrate holder. This apparatus is a method in which a substrate holder attached with a substrate traverses during sputtering to process a large number of substrates. .

[0003]

In recent years, in the manufacture of a mounting substrate on which an LSI is mounted or a matrix substrate used for a liquid crystal device, it is required to uniformly form a large area of a thin film used for a wiring layer or a resistance layer and to have high throughput. There is.

The thin film formed by the above-mentioned conventional technique has a uniform distribution in the horizontal direction (moving direction) by the rotation of the substrate holder, but the film thickness distribution in the vertical direction is the film thickness distribution shown in FIG. There is. As can be seen from this figure, as shown in (a), there may be a case where the top and bottom are thin and the vicinity of the center is thin in the substrate holder, and as shown in (b), the center part may be thin, contrary to (a). Therefore, in order to obtain a substrate with a good film thickness distribution, the size of the substrate, that is, the film formation region becomes small,
There is a problem that the throughput does not rise. As a method of solving this problem, there are a method of enlarging the sputtering target and enlarging the good region of the film thickness distribution, and a method of correcting the magnet in the magnetron system to change the strength of the magnetic field and change the distribution shape. But,
This method requires a major modification of the equipment to use the existing equipment. In addition, it is very difficult to reproduce the film thickness distribution by the method.

The present invention solves the above problems,
It is intended to provide a thin film forming method capable of reducing manufacturing cost and improving throughput.

[0006]

To incline the substrate with respect to the target in a plane perpendicular to the moving direction of the substrate when the moving direction of the substrate is parallel to the target. That is, in the case of the apparatus having the distribution shown in FIG. 11A, the film is formed by mounting the substrate so that the thick portion (near the center) in the holder is separated from the target. In the case of the apparatus having the distribution shown in FIG. 11B, the substrate is attached in such a manner that the thin portion (near the center) in the holder is close to the target to form the film. In order to make the effect clearer, the height difference between the edge and the center of the substrate holder has a remarkable effect, but there is a limit to this height difference due to the structure of the device, etc. Must be 45 ° or less.

[0007]

With the above means, the thin film portion becomes thicker by approaching the target surface, and the thick film portion becomes thinner by moving away from the target. Therefore, by inclining the substrate, the distance between the target and the substrate can be changed within the plane of the substrate, and the film thickness can be made uniform.

[0008]

【Example】

(Example 1) As shown in FIG. 1, in a conventional carousel type (side sputtering) sputtering apparatus,
Part of the substrate holder that rotates parallel to the sputtering target can be removed, and the removed substrate holder has a height difference of 10 m between the upper and lower ends and the center as shown in FIG.
When the cross section of the substrate holder was attached, the structure was such that it was bent from the center to form a V shape. When a substrate having a size of 5 inches square or more was attached to this substrate holder as shown in FIG.
The film thickness distribution as shown by the line b was obtained. The film thickness distribution by the conventional method is shown by the line a in FIG. As can be seen from this figure, the difference in film thickness between the lower end of the holder and the central part was small, and a good distribution was obtained.

According to this embodiment, it is possible to prevent the film thickness reduction characteristic of the upper and lower end portions of the substrate holder peculiar to the sputtering apparatus.

(Embodiment 2) As shown in FIG. 3, in a conventional carousel type (side sputtering) sputtering apparatus, a part of a substrate holder rotating parallel to a sputtering target can be removed, and the removed substrate The holder was divided into three parts as shown in FIG.
Three 3-inch square substrates were mounted in the holder as shown in FIG. 3 to form a film. As a result, the film thickness distribution as shown by the line c in FIG. 5 was obtained. As can be seen from this figure, the difference in film thickness between the upper and lower parts and the central part of the three substrates was small, and a good distribution was obtained.

That is, by forming the substrate holder into a shape, it is possible to form a film on a plurality of substrates and improve the throughput.

According to the first and second embodiments, it is possible to prevent the film thickness reduction characteristic at the upper and lower ends of the substrate holder, which is peculiar to the sputtering apparatus. As a result, it is possible to increase the size of at least the substrate that is half the length of the used target in the vertical direction. Further, it is possible to solve the problem of variation in the film thickness distribution between the same film formation substrates and improve the throughput.

FIG. 6 shows the structure of the substrate holder when the above-mentioned substrate holder has an operative structure, that is, when the height difference between the upper and lower end portions and the central portion of the substrate holder can be adjusted. As a structure, a jig that can adjust the angle is attached to the bent part of the holder. By using this substrate holder, the film thickness distribution can be controlled, and the specific resistance of the thin film can be made uniform.

[0014]

As described above, according to the present invention, the film thickness distribution peculiar to the sputtering apparatus can be controlled, so that the film formation effective area and the film formation substrate can be increased by 1.5 to 2 times. Further, the same effect can be obtained for a sputtering device other than the above.

[Brief description of drawings]

FIG. 1 is a diagram showing a positional relationship between a target and a substrate when Example 1 of the present invention is viewed from above (a) and when viewed from the side (b).

FIG. 2 is a diagram showing a substrate holder according to the first embodiment of the present invention.

FIG. 3 is a diagram showing a positional relationship between a target and a substrate in Embodiment 2 of the present invention as viewed from above (a) and viewed from the side (b).

FIG. 4 is a diagram showing a substrate holder according to a second embodiment of the present invention.

FIG. 5 is a diagram showing a film thickness distribution of thin films formed according to Examples 1 and 2 of the present invention and a conventional example.

FIG. 6 is a diagram showing a movable substrate holder of the present invention.

FIG. 7 is a diagram showing a first conventional example of a sputtering apparatus.

FIG. 8 is a diagram showing a positional relationship between a target and a substrate in a case where the first conventional example is viewed from above (a) and when viewed from the side (b).

FIG. 9 is a diagram showing a second conventional example of a sputtering apparatus.

FIG. 10 is a diagram showing a positional relationship between a target and a substrate in a case where the second conventional example is viewed from above (a) and when viewed from the side (b).

FIG. 11 is a diagram showing a film thickness distribution according to a conventional technique.

[Explanation of symbols]

1 ... Substrate holder, 2 ... Substrate, 3 ... Substrate holder (tray type), 4 ... Substrate holding jig, 5 ... Substrate holder holding jig, 6 ... Bending jig, 7 ... Vacuum chamber, 8 ... Sputtering cathode, 9 ... Sputtering target, 10 ...
High frequency power source, 11 ... Vacuum chamber frame, 12 ... Substrate transfer jig, 1
00 ... Holder rotation direction, 200 ... Holder movement direction, 3
00 ... Enlarged view (FIG. 2), 400 ... Enlarged view (FIG. 4).

Claims (5)

[Claims] 1. A method for forming a thin film by a sputtering method, wherein a thin film is formed on a substrate while facing and moving the substrate to the target, and when the moving direction of the substrate is parallel to the target. A method of forming a thin film, comprising forming the thin film in a plane perpendicular to the moving direction of the substrate, and inclining the substrate with respect to the target. 2. The method for forming a thin film according to claim 1, wherein an inclination angle for inclining the substrate is 45 degrees or less with respect to a target surface. 3. A sputtering apparatus comprising a substrate supporting mechanism (substrate holder) for realizing the thin film forming method according to claim 1. 4. A substrate holder surface on which a thin film is simultaneously formed is composed of at least two substrate supporting surfaces, and each of the substrate supporting surfaces can be independently inclined. Sputtering equipment. 5. The sputtering apparatus according to claim 4, wherein a substrate supporting surface parallel to the target is provided on a substrate holder surface on which a thin film is simultaneously formed.